0001193125-21-332868 | S-1 | XBRL Viewer | Greenidge Generation Holdings INC

Merger with Support

MERGER WITH SUPPORT

As described in Note 1, on September 14, 2021, Greenidge and Support combined their respective businesses through an

all-stock

merger transaction where Support became a wholly owned subsidiary of Greenidge. The merger has been accounted for as a business combination using the acquisition method of accounting in accordance with the provisions of FASB ASC 805,

Business Combinations

(“ASC 805”). Greenidge was determined to be the acquiring company for accounting purposes.

At the effective time of the Merger (“Effective Time”): (i) each share of common stock of Support (the “Support Common Stock”) issued and outstanding immediately prior to the Effective Time was cancelled and extinguished and automatically converted into the right to receive 0.115 (the “Exchange Ratio”) shares of class A common stock, par value $0.0001, of the Company, (ii) each outstanding stock option of Support immediately prior to the Effective Time (an “Option”) was accelerated, and the holder of each Option received the right to receive an amount of the Company’s class A common stock equal to the Exchange Ratio, multiplied by the number of shares of Support Common Stock underlying such Option, less any shares withheld in satisfaction of the aggregate exercise price of such Option and such holder’s tax withholding obligations and (iii) each outstanding restricted stock unit of Support immediately prior to the Effective Time (an “RSU”) was accelerated, and the holder of each RSU received the right to receive an amount of the Company’s class A common stock equal to the Exchange Ratio, multiplied by the number of shares of Support Common Stock underlying such RSU, less any shares and such holder’s tax withholding obligations.

Preliminary Allocation of the Purchase Price

We have applied the acquisition method of accounting in accordance with ASC 805, with respect to the identifiable assets and liabilities of Support, which have been measured at estimated fair value as of the date of the business combination. Any excess of the acquisition price over the fair value of the assets and liabilities acquired is recorded as goodwill.

As required by ASC 805, the acquisition price was determined based on the value of the consideration paid to Support shareholders, calculated to be $93.9 million (see table below). This acquisition price was allocated to the identifiable assets acquired and liabilities assumed of Support based upon their estimated fair values at the Merger date, primarily using Level 2 and Level 3 inputs. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable, and Level 3 inputs are inputs that are unobservable (for example, cash flow modeling inputs based on assumptions). Due to the timing of the business combination, allocations of the acquisition price are based on preliminary estimates and assumptions at the Merger date and are subject to revision based on final information received, including appraisals, projections and other analysis which support underlying estimates. As the Company finalizes the fair value of assets acquired and liabilities assumed, additional purchase price allocation adjustments may be recorded during the measurement period, but no later than one year from the date of the Merger. The Company will reflect measurement period adjustments in the period in which the adjustments are determined.

The following table summarizes the estimated value of the consideration paid (purchase price):


$ in thousands, except per share amount
Support common stock exchanged		25,745,487
Exchange ratio		0.115

Greenidge Class A common stock exchanged		2,960,731
Greenidge common stock value per share	$	31.71

Consideration paid	$	93,885

For the period immediately prior to the effective date of the Merger, Greenridge was a private company, and Support’s stock price fluctuated significantly based on factors not representative of the value of its underlying operations; therefore, Greenidge used the average of its closing stock price for the first ten days of trading on the Nasdaq Exchange ($31.71 per share) to measure the value of the consideration paid to Support shareholders.

The following table summarizes the preliminary allocation of the purchase price to the identifiable assets acquired and liabilities assumed by Greenridge, with the excess of the purchase price over the fair value of Support’s net assets recorded as goodwill. As previously discussed, allocations of the acquisition price are based on preliminary estimates and assumptions and the final determination of the fair values may result in further adjustments to the values presented in the following table:


$ in thousands
Cash and cash equivalents	$	27,113
Short-term investments		496
Accounts receivable		5,383
Prepaid expenses and other current assets		713
Property and equipment		1,349
Other long-term assets		383
Accounts payable		(117	)
Accrued expenses and other current liabilities		(3,328	)
Other long-term liabilities		(242	)
Intangible assets		22,690
Deferred tax liability		(6,904	)
Goodwill		46,349

Total consideration	$	93,885

For assets and liabilities (excluding identifiable intangible assets and deferred revenues), the Company estimated that the carrying values, net of allowances, represented the fair values at the effective date of the Merger.

The fair value estimates for identifiable intangible assets is based on preliminary assumptions that market participants would use in pricing an asset, based on the most advantageous market for the asset (i.e., its highest and best use). The final fair value determination for identifiable intangibles or estimates of remaining useful lives may differ materially from this preliminary determination. Following is a summary of identifiable intangible assets determined on a preliminary basis and is subject to adjustment during the measurement period, which could be material:


$ in thousands
Identifiable Intangible Asset	Useful Life		Fair Value
Customer relationships		5 years	$	21,600
Tradename		10 years		1,090

Total identifiable intangible assets			$	22,690

The preliminary fair value of the customer relationships intangible asset was valued using a multi-period excess earnings method, a form of the income approach, which incorporates the estimated future cash flows to be generated from Support’s existing customer base. Excess earnings are the earnings remaining after deducting the market rates of return on the estimated values of contributory assets, including debt-free net working capital, tangible assets, and other identifiable intangible assets. The excess earnings are thereby calculated for each year of multi-year projection periods and discounted to present value.

The preliminary fair value of the Support tradename was valued using the relief from royalty method under the income approach. This method estimates the cost savings generated by a company related to the ownership of an asset for which it would otherwise have had to pay royalties or license fees on revenues earned through the use of the asset and discounted to present value.

Due to the timing of the Merger, the Company is in the early stages of its purchase accounting process. As the Company completes this process, including the finalization of the purchase price, fair value calculations, and a more detailed assessment of Support’s business projections, any measurement period adjustments will be recorded and a goodwill impairment test will be performed. In accordance with ASC 805, Support’s assets and liabilities are recorded at fair value at September 14, 2021, and accordingly, there is no cushion between Support’s fair value and carrying value. Considering that the fair value used to determine the consideration was based upon a stock that experienced significant price fluctuations, it is possible that goodwill and intangible assets may need to be impaired at that time.

Results of Support Operations Since the Merger

For the three and nine months ended September 30, 2021, the acquired Support business contributed $1.5 million in revenue and an immaterial operating loss, which includes approximately $0.2 million of amortization expenses of acquired intangible assets.

Supplemental Pro Forma Financial Information

In accordance with ASC 805, the following supplemental unaudited pro forma information gives effect to the Merger as if it had occurred on January 1, 2020. The unaudited pro forma financial information reflects certain adjustments related to the acquisition, such as:

•

Conforming the accounting policies of Support to those applied by Greenidge;

•

Recording certain incremental expenses resulting from purchase accounting adjustments, such as amortization expense in connection with fair value adjustments to intangible assets; and

•

Recording the related tax effects of pro forma adjustments.


	Three Months Ended September 30,						Nine Months Ended September 30,
$ in thousands	2021			2020			2021			2020
Revenues	$	42,448		$	16,461		$	87,830		$	47,258
Net (loss) income	$	(11,783	)	$	(1,646	)	$	(12,602	)	$	(6,274	)

The pro forma results for three and nine months ended September 30, 2021 include $30.0 million and $32.4 million, respectively, of transaction costs for both Greenidge and Support ($24.5 million and $26.9 million after tax, respectively), such as advisor fees, legal and accounting expenses. These costs will not affect the combined company’s statement of operations beyond 12 months after the closing date, September 14, 2021. See Note 4 for additional information.

The unaudited pro forma financial information should not be relied upon as being indicative of the historical results that would have been obtained if the Merger had actually occurred on that date, nor the results of operations of the Company in the future.

MERGER AND OTHER COSTS

9 Months Ended

Sep. 30, 2021

MERGER AND OTHER COSTS

The following table provides details of Merger and other costs for the three and nine months ended September 30, 2021:


	Three Months Ended		Nine Months Ended
$ in thousands	September 30, 2021		September 30, 2021
Merger related costs:
Investor fee paid in common stock (Note 9)	$	17,826	$	17,826
Advisor fee paid in warrants (Note 9)		8,779		8,779
Professional and other fees		1,140		1,434

Total Merger related costs		27,745		28,039
Public company filing related costs		2,102		3,056

Total Merger and other costs	$	29,847	$	31,095

SEGMENT INFORMATION

9 Months Ended

Sep. 30, 2021

Segment Reporting [Abstract]

SEGMENT INFORMATION

Effective September 14, 2021, following the completion of the Merger (see Notes 1 and 3), Support began operating within the Greenidge structure as a separate operating and reporting segment; therefore, Greenidge has two operating and reportable segments since the acquisition: i) Cryptocurrency Mining and Power Generation and ii) Support Services as the other. Prior to the Merger, Greenidge operated in one operating and reporting segment, Cryptocurrency Mining and Power Generation.

The Cryptocurrency Mining and Power Generation segment operates in the United States and generates revenue primarily by earning bitcoin, with application-specific integrated circuit computers (“ASICs” or “miners”) that are owned by the Company, as rewards and transaction fees for supporting the global bitcoin network. The Cryptocurrency Mining and Power Generation segment also sells surplus electricity generated by its power plant, and not consumed in bitcoin mining operations, to the New York Independent System Operator (“NYISO”) power grid at prices set on a daily basis through the NYISO wholesale market. In addition, the Company receives revenues from the sale of its capacity and ancillary services in the NYISO wholesale market. The Cryptocurrency Mining and Power Generation segment operates in the United States

The Support Services segment provides solutions and technical programs to customers delivered by home-based employees. The Support Services segment provides customer service, sales support, and technical support primarily to large corporations, businesses and professional services organizations. The Support Services segment also earns revenues for

end-user

software products provided through direct customer downloads and sale via partners. The Support Services segment operates primarily in the United States, but also has employees located in Philippines, India, Mexico, Colombia and Canada, including those staff providing support services.

The Company’s measure of profit or loss for segment reporting is income (loss) before income taxes, interest and depreciation and amortization and adjusted for share based compensation and excluding items not indicative of ongoing business trends (referred to as “segment Adjusted EBITDA”). This is the measure used by the Chief Operating Decision Maker (“CODM”) to assess performance and allocate resources.

The table below presents information about reportable segments for the three and nine months ended September 30, 2021 and 2020, respectively:


	Three Months Ended September 30,				Nine Months Ended September 30,
$ in thousands	2021		2020		2021		2020
Revenues:
Cryptocurrency Mining and Power Generation	$	34,233	$	6,123	$	61,472	$	13,937
Support Services		1,521		—		1,521		—

Total Revenues	$	35,754	$	6,123	$	62,993	$	13,937

Segment Adjusted EBITDA
Cryptocurrency Mining and Power Generation	$	20,973	$	775	$	33,464	$	1,301
Support Services		204		—		204		—

Total Segments Adjusted EBITDA	$	21,177	$	775	$	33,668	$	1,301

In addition, the table below provides a reconciliation of the total of the segments Adjusted EBITDA to the consolidated Loss before income taxes:


	Three Months Ended September 30,						Nine Months Ended September 30,
$ in thousands	2021			2020			2021			2020
Total Segments Adjusted EBITDA	$	21,177		$	775		$	33,668		$	1,301
Depreciation and amortization		(2,667	)		(1,064	)		(5,531	)		(3,227	)
Stock-based compensation		(411	)		—			(1,474	)		—
Merger and other costs		(29,847	)		—			(31,095	)		—
Expansion costs		(128	)		—			(128	)		—
Interest expense, net		(1,009	)		—			(1,399	)		(540	)

Consolidated loss before income taxes	$	(12,885	)	$	(289	)	$	(5,959	)	$	(2,466	)

The table below provides segment assets, which exclude cash and

cash

equivalents and short term investments, and a reconciliation to the consolidated total assets of the Company:


$ in thousands	September 30, 2021
Cryptocurrency Mining and Power Generation		129,802
Support Services		76,864

Total segment assets		206,666
Cash and cash equivalents		51,149
Short term investments		496

Total assets	$	258,311

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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Property, Plant and Equipment [Abstract]

PROPERTY AND EQUIPMENT

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Property and Equipment

PROPERTY AND EQUIPMENT

Property and equipment, net consisted of the following at September 30, 2021 and December 31, 2020:


$ in thousands	Estimated Useful Lives		September 30, 2021			December 31, 2020
Plant infrastructure		15 - 39 years	$	34,273		$	33,944
Miners		5 years		36,779			10,236
Miner facility infrastructure		15 years		14,787			8,791
Land		N/A		300			300
Equipment		5 years		948			211
Software		3 years		1,130			66
Coal ash impoundment		4 years		2,135			2,135
Construction in process		N/A		6,869			3,989
Miner deposits		N/A		38,467			5,959

				135,688			65,631
Less: Accumulated depreciation				(14,156	)		(8,986	)

			$	121,532		$	56,645

Total depreciation expense was $2.7 million and $5.5 million for the three and nine months ended September 30, 2021 and was $1.1 million and $3.2 million for the three and nine months ended September 30, 2020, respectively.

PROPERTY AND EQUIPMENT

Property and equipment, net consisted of the following at December 31:


	Estimated Useful Lives		2020			2019
Plant infrastructure		15 – 39 years	$	33,944		$	31,387
Miners		5 years	$	10,236			—
Miner Facility		15 years		8,791			—
Land		N/A		300			300
Equipment		5 years		211			206
Software		3 years		66			66
Coal ash impoundment		4 years		2,135			2,135
Construction in process		N/A		3,989			7,392

				59,672			41,486
Less: Accumulated depreciation				(8,986	)		(4,422	)

			$	50,686		$	37,064

Total depreciation expense was $4,564 and $1,679 for the years ended December 31, 2020 and 2019, respectively.

NOTES PAYABLE

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Debt Disclosure [Abstract]

Notes Payable

NOTES PAYABLE

The Company has entered into equipment finance agreements that are secured by the purchased miner equipment. These agreements generally require monthly payments of principal, interest and a risk premium fee. The following table provides information on the equipment financing agreements:


$ in thousands
					Interest Rate			Initial Financing		Balance as of:
Note	Loan Date		Maturity Date		Interest Rate			Initial Financing		September 30, 2021			December 31, 2020
A		December 2020		June 2022		17.0	%	$	4,482	$	1,992		$	4,233
B		December 2020		June 2022		17.0	%		428		166			404
C		March 2021		November 2022		17.0	%		2,229		1,733			—
D		April 2021		December 2022		17.0	%		4,012		3,343			—
E—H		May 2021		October 2023		15.0	%		12,080		11,751			—
I		July 2021		January 2023		17.0	%		4,457		3,962			—
J		July 2021		March 2023		17.0	%		2,701		2,415			—

											25,363			4,637
Less: Current portion											(17,994	)		(3,273	)

										$	7,369		$	1,364

The Company incurred interest expense of $1.0 million and $1.4 million during the three and nine months ended September 30, 2021, respectively, under the terms of these notes payable.

NOTES PAYABLE

The Company entered into an equipment finance agreement during December 2020 to finance miner equipment purchases totaling $4,482 with a third-party (“Miner equipment note A”). The terms of the financing agreement require interest at 17% per annum, including a risk premium fee of $482. The note requires principal payments of $222, risk premium payments of $27, and variable amounts of interest, every 30 days through the maturity date in July 2022. The note is secured by the purchased equipment.

The Company entered into an equipment finance agreement during December 2020 to finance miner equipment purchases totaling $428 with a third-party (“Miner equipment note B”). The terms of the financing agreement require interest at 17% per annum and principal payments of $24, plus variable amounts of interest, every 30 days through the maturity date in June 2022. The note is secured by the purchased equipment.

The Company entered into three other equipment finance agreements with similar terms in December 2020 that have not yet taken effect as of December 31, 2020. The agreements are expected to take effect when the equipment is delivered to the Company, which is expected in the second quarter of 2021. The aggregate amount of equipment and principal borrowings under the three agreements is $10,698.

As of December 31, 2019, there were no notes payable outstanding. Notes payable consisted of the following at December 31, 2020:


Miner equipment note A	$	4,233
Miner equipment note B		404

		4,637
Less: Current portion		(3,273	)

	$	1,364

Future maturities of notes payable are as follows for the years ending December 31:


2021	$	3,273
2022		1,364

	$	4,637

The Company incurred interest expense of $91 during the year ended December 31, 2020 under the terms of these notes payable.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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Related Party Transactions

RELATED PARTY TRANSACTIONS

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

RELATED PARTY TRANSACTIONS

Notes Payable

The Company entered into a promissory note agreement during 2020 with its largest equity members, Atlas Capital Resources LP and Atlas Capital Resources (P) LP (collectively referred to herein as “Atlas”). Within the agreement, there were two separate loans. One of these related party loans had a June 2021 maturity and a balance of $2.4

illion

at December 31, 2020, and the other loan had a May 2021 maturity with a balance of $1.2

lion

Notes Payable

December 31, 2020. The promissory notes bore interest at

per annum calculated on a

360-day

year, and interest accrued and compounded on a quarterly basis. All accrued but unpaid interest under the notes was due and payable upon the corresponding note maturity date. Under this promissory note agreement, the Company incurred an immaterial amount of interest expense during the nine months ended September 30, 2021. During the nine months ended September 30, 2020, the Company incurred interest expense of $0.5 million associated with the loans that were converted into senior priority units in July 2020.

Notes payable to related party consisted of the following:


$ in thousands	September 30, 2021		December 31, 2020
Note payable to a related party due June 2021	$	—	$	2,382
Note payable to a related party due May 2021		—		1,191

	$	—	$	3,573
Less: Current Portion	$	—	$	(3,573	)

	$	—	$	—

The related party loans in the table above were converted into Greenidge common stock in January 2021 (see Note 9).

Letters of Credit

On March 19, 2021, the Company and Atlas and its affiliates entered into an arrangement pursuant to which Greenidge agreed, upon request, to direct its bank to issue new letters of credit to replace all or a portion of the letters of credit provided by Atlas and certain of its affiliates, upon the consummation of a potential investment in, financing of, or sale of any assets or equity or debt securities of the Company, which results in net proceeds to the Company of at least $10

million

Atlas obtained a letter of credit from a financial institution in the amount of $5.0

million at September 30, 2021, payable to the NYSDEC. This letter of credit guarantees the current value of the Company’s environmental trust liability as discussed in Note 2.

Atlas also obtained a letter of credit from a financial institution in the amount of $3.6

million at September 30, 2021, payable to Empire Pipeline Incorporated (“Empire”) in the event the Company should not make contracted payments for costs related to a pipeline interconnection project the Company has entered into with Empire (see Note 13).

Guarantee

An affiliate of Atlas has guaranteed the payment obligation of Greenidge in favor of Emera Energy Services, Inc. under an Energy Management Agreement and an ISDA Master Agreement under which Greenidge may enter into various transactions involving the purchase and sale of gas, electricity and other commodities with Emera Energy Services, Inc. This guaranty is limited

to $1.0

million. Atlas had no exposure under the guarantee during the period ended September 30, 2021.

Greenidge Coin, LLC Equity Transactions

On October 2, 2019, Blocker, a related entity through common ownership, purchased 15,000 preferred units of GC for $15

thousand.

On July 1, 2020, Atlas purchased the preferred units of Blocker for $

16.3

million, the amount of the aggregate liquidation preference, and contributed its membership interest in Blocker to GGH in exchange for Senior Priority Units – Tranche 2 (See Note 9) on July 2, 2020.

On December 31, 2020, Blocker entered into a liquidating distribution agreement with GGH, effectively dissolving Blocker into GGH.

RELATED PARTY TRANSACTIONS

Notes Payable

The Company entered into a promissory note agreement during the year ended December 31, 2019 with its largest equity members, Atlas Capital Resources (A9) LP and Atlas Capital Resources (P) LP (together referred to as “Atlas”). Within the agreement, there were three separate loans with varying loan amounts and maturity dates. The notes bore interest at 8% per annum calculated on a

360-day

year, and interest accrued and compounded on a quarterly basis. On July 2, 2020, the Company entered into a contribution and exchange agreement with Atlas, and the three notes payable and related accrued interest was converted into equity in the form of Senior Priority Units – Tranche 1. The Company incurred interest expense of $553 and $673 under the terms of this promissory note agreement for the years ended December 31, 2020 and 2019, respectively.

The Company entered into a promissory note agreement during 2020 with its largest equity members, Atlas. Within the agreement, there are two separate loans with varying loan and maturity dates as described in the table below. The notes bear interest at 8% per annum calculated on a

360-day

year, and interest accrues and compounds on a quarterly basis. All accrued but unpaid interest under the notes is due and payable upon the corresponding note maturity date. For the year ended December 31, 2020, the Company incurred interest expense of $20 under the terms of this promissory note agreement.

Notes payable to related party consisted of the following at December 31:


	2020			2019
Note payable to a related party with interest at 8% per annum. All outstanding principal and accrued but unpaid interest is due June 2021.	$	2,382		$	—
Note payable to a related party with interest at 8% per annum. All outstanding principal and accrued but unpaid interest is due May 2021.		1,191			—
Notes payable converted into Senior Priority Units—Tranche 1 (see Note 6).		—			12,700

		3,573			12,700
Less: Current portion		(3,573	)		(5,000	)

	$	—		$	7,700

Letters of Credit

The largest equity members of the Company, Atlas Capital Resources LP and Atlas Capital Resources (P) LP, obtained a letter of credit from a financial institution in the amount of $4,938 at December 31, 2020 and 2019, payable to the NYSDEC. This letter of credit guarantees the current value of the Company’s environmental trust liability as discussed in Note 2.

Atlas Capital Resources LP and Atlas Capital Resources (P) LP also obtained a letter of credit from a financial institution in the amount of $3,630 at December 31, 2020 and 2019, payable to Empire Pipeline Incorporated (“Empire”) in the event the Company should not make contracted payments for costs related to a pipeline interconnection project the Company has entered into with Empire.

The Company paid Atlas Capital Resources LP and Atlas Capital Resources (P) LP $184 and $206 for letter of credit fees during the years ended December 31, 2020 and 2019, respectively.

Greenidge Coin, LLC Equity Transactions

On October 2, 2019, Blocker, a related entity through common ownership, purchased 15,000 preferred units of GC for $15,000.

On July 1, 2020, Atlas purchased the preferred units of Blocker for $16,277, the amount of the aggregate liquidation preference, and contributed its membership interest in Blocker to GGH in exchange for Senior Priority Units—Tranche 2 (See Note 6) on July 2, 2020.

On December 31, 2020, Blocker entered into a liquidating distribution agreement with GGH, effectively dissolving Blocker into GGH.

STOCKHOLDERS' EQUITY

9 Months Ended

Sep. 30, 2021

Stockholders' Equity Note [Abstract]

Stockholders Equity

STOCKHOLDERS’ EQUITY

Authorized Shares

On September 13, 2021, Greenidge filed an amendment to its certificate of incorporation to increase the authorized capital stock. Pursuant to the amended and restated certificate of incorporation, Greenidge’s authorized capital stock consists of

2,400,000,000

shares of class A common stock, par value

$0.0001 p

share, 600,000,000

shares of class B common stock, par value

$0.0001 per share, and 20,000,000

shares of preferred stock, par value

$0.0001 per share

Contribution and Exchange Agreement

In January 2021, GGH completed a corporate restructuring. Pursuant to this restructuring, Greenidge was formed and incorporated in the State of Delaware on January 27, 2021. On January 29, 2021, Greenidge entered into an asset contribution and exchange agreement with the members of GGH, in which the GGH members’ equity interests and outstanding notes payable to related parties and all accrued but unpaid interest were contributed into Greenidge in exchange for 7,000,000 shares of Greenidge class B common stock (28,000,000 shares following the

4-for-1

stock split noted below) (see Note 8). As a result of this transaction, GGH became a wholly owned subsidiary of Greenidge.

Private Placement Offering of Preferred Stock

In January 2021, Greenidge completed a private placement offering in which 1,620,000 shares of series A redeemable convertible preferred stock was sold at $25 per share. Total net proceeds from the private placement offering were $37.1 million.

Under the terms of the private placement memorandum in connection with the preferred stock offering, each share of preferred stock was automatically converted to four shares of class B common stock when the Company’s registration statement to register such shares for resale was declared effective by the Securities and Exchange Commission. During September 2021, this preferred stock was converted into 5,760,000 shares of class A common stock and 720,000 shares of class B common stock. There are no outstanding shares of preferred stock as of September 30, 2021.

Equity Issuances Associated with the Merger

In connection with the completion of the Merger, we issued 2,960,731 shares of class A common stock in consideration for all of the outstanding shares of Support. The fair value of the common shares issued to Support shareholders was $93.9 million (see Note 3), or $91.6 million, net of issuance costs.

Additionally, pursuant to the Merger Agreement, we issued the following equity instruments in connection with the performance of consulting services leading to and in connection with the Merger at the time of the closing, as the issuance of these instruments were contingent upon successful completion of the Merger:

•

562,174 shares of class A common stock with a fair value of $17.8 million issued to an investor, which owned approximately 16.6% of Support common stock and made a prior investment in Greenidge preferred stock, which was described previously; and

•

Warrants to purchase 344,800 shares of class A common stock at an exercise price of $6.25 per share of class A common stock to B. Riley Securities, Inc., which were exercised shortly thereafter. The fair value of the warrants at issuance was $8.8 million.

Equity Purchase Agreement with B. Riley Principal Capital, LLC

On September 15, 2021, Greenidge entered into a common stock purchase agreement (the “Purchase Agreement”) with B. Riley Principal Capital, LLC (the “Investor”) pursuant to which Greenidge has the right to “put” or sell to the Investor up to $500 million of shares of class A common stock, subject to certain limitations and conditions set forth in the Purchase Agreement, from time to time during the term of the Purchase Agreement. Under the applicable Nasdaq rules, in no event may Greenidge issue to the Investor under the Purchase Agreement more than 19.99% of the total number of combined shares of its class A common stock and class B common stock that were outstanding immediately prior to the execution of the Purchase Agreement (the “Exchange Cap”), unless Greenidge obtains stockholder approval to issue shares in excess of the Exchange Cap in accordance with applicable Nasdaq rules.

The per share purchase price for the shares of class A common stock that Greenidge elects to sell to the Investor pursuant to the Purchase Agreement will be determined by reference to the volume weighted average price of class A common stock (“VWAP”) during the applicable purchase date on which Greenidge has timely delivered written notice to the Investor directing it to purchase shares under the Purchase Agreement, less a fixed 5% discount, which shall be increased to a fixed 6% discount at such time that Greenidge received aggregate cash proceeds of $200 million as payment for all shares of class A common stock purchased by the Investor in all prior sales of class A common stock made under the Purchase Agreement. The Investor will have no obligation to purchase shares pursuant to the Purchase Agreement to the extent that such purchase would cause the Investor to own more than 4.99% of Greenidge’s issued and outstanding shares of class A common stock.

In connection with the Purchase Agreement, Greenidge entered into a registration rights agreement with the Investor pursuant to which Greenidge agreed to prepare and file a registration statement registering the resale by the Investor of those shares of Greenidge’s class A common stock to be issued under the Purchase Agreement. The registration statement became effective on October 6, 2021 relating to the resale of

3,500,000

shares of Greenidge’s class A common stock in connection with this Purchase Agreement.

Common Stock

Holders of Greenidge’s class A common stock are entitled to one vote per share. Holders of class B common stock are entitled t

o ten votes

per share. Class A and class B shares issued and outstanding as of September 30, 2021

are 9,627,705 and 29,040,000, respectively.

Each share of class B common stock is convertible into one share of class A common stock at the option of the holder upon written notice to the Company. Shares of class B common stock will automatically convert to shares of class A common stock upon a mandatory conversion event as defined in the amended and restated certificate of incorporation dated March 26, 2021.

Common Units

In October 2018, GGH adopted an equity incentive plan and allocated 1,250 common units to the plan. In 2018, GGH awarded 750 restricted units to certain board members, subject to various vesting provisions. At December 31, 2020, there were 730 and 20 vested and unvested, respectively, restricted units. In the event of a change in control of the Company, 100% of the awarded units would vest immediately. Common unit holders are entitled to one vote per common unit, except for such votes or consents that are reserved solely for the holders of preferred units.

The

Company concluded that the value of the units granted in 2018 was insignificant given historical performance of the Company, no public market, and lack of liquidity. As such, the Company

did not

recognize any expense related to the common restricted units during the three and nine months ended September 30, 2021 and 2020. There

were 750

common units issued and outstanding at December 31, 2020. In January 2021, in conjunction with the private placement offering, the 750 GGH common units were converted to shares of Greenidge’s class B common stock.

Preferred Units

GGH preferred unit holders were entitled to one vote per preferred unit. In the event of liquidation or dissolution of GGH, the holders of preferred units were entitled to receive distributions, prior to and in preference to the holders of common units. At December 31, 2020, all preferred units were issued and outstanding. All preferred units were converted to shares of Greenidge’s class B common stock in connection with the contribution and exchange agreement.

Senior Priority Units

There were two tranches of

Senior Priority Units: Tranche 1 was equal to $13.9

million

and Tranche 2 was equal to $16.3

lion

. Tranche 1 Senior Priority Units were issued to Atlas in July 2020 in exchange for the conversion of certain notes payable due to Atlas and all accrued but unpaid interest thereon. Tranche 2 Senior Priority Units were issued to Atlas in conjunction with Atlas contributing its equity interest in Blocker to GGH. Senior Priority Units had no voting rights.

At December 31, 2020, all senior priority units were issued and outstanding. All senior priority units were converted to shares of Greenidge’s class B common stock in connection with the contribution and exchange agreement.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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Share-based Payment Arrangement [Abstract]

MEMBERS' EQUITY

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Members' Equity

MEMBERS’ EQUITY

Authorized Units

On July 2, 2020, GGH amended and restated its LLC agreement. The Company is authorized to issue 1,250 common units, 39,228 preferred units, and 10,000 senior priority units.

Common Units

2020, there

were 730 and 20 vested and

unvested,

respectively, restricted units. At December 31, 2019, there were 600 and 150 vested and unvested, respectively, restricted units. In the event of a change in control of the Company, 100% of the awarded units shall vest immediately. Common unit holders are entitled to one vote per common unit, except for such votes or consents that are reserved solely for the holders of preferred units. The Company concluded that the value of the units granted in 2018 was insignificant given historical performance of the Company, no public market, and lack of liquidity. As such, the Company has not recognized any expense related to the restricted units during the years ended December 31, 2020 or 2019. There were 750 common units issued and outstanding at both December 31, 2020 and 2019.

Preferred Units

Preferred unit holders are entitled to one vote per preferred unit. In the event of liquidation or dissolution of GGH, the holders of preferred units are entitled to receive distributions, prior to and in preference to the holders of common units. At December 31, 2020 and 2019, all preferred units were issued and outstanding.

In the event of liquidation or dissolution of GGH, the holders of preferred units are entitled to receive distributions, prior to and in preference to the holders of common units, in an amount equal to $1 per preferred unit.

Senior Priority Units

There are two tranches of Senior Priority Units: Tranche 1 is equal to $13,926 and Tranche 2 is equal to $16,276. Tranche 1 Senior Priority Units were issued to Atlas Capital Resources LP and Atlas Capital Resources (P) LP in the same historical ownership percentages in conjunction with Atlas converting the 2019 notes payable and accrued interest (see Note 5). Tranche 2 Senior Priority Units were issued to Atlas Capital Resources LP and Atlas Capital Resources (P) LP in the same historical ownership percentages in conjunction with Atlas contributing its equity interest in Blocker (see Note 5). Senior Priority Units have no voting rights.

In the event of liquidation or dissolution of GGH, the holders of senior priority units are entitled to receive distributions, prior to and in preference to the holders of common and preferred units. The holders of senior priority units are entitled to a cumulatively accrued rate of return on the investment of 8% in addition to the initial output of $13,926. The aggregate liquidation preference on GGH’s senior priority units was $14,498 at December 31, 2020.

At December 31, 2020, all senior priority units were issued and outstanding.

EMPLOYEE BENEFIT PLAN

12 Months Ended

Dec. 31, 2020

Retirement Benefits [Abstract]

Employee Benefit Plan

EMPLOYEE BENEFIT PLAN

GG sponsors a 401(k) plan (the Plan) covering substantially all GG employees. Employees become eligible to participate in the Plan upon the attainment of age

twenty-one.

Eligible employees may elect to make either

pre-tax

or Roth contributions to the Plan, subject to limitations set forth by the Plan and the Internal Revenue Code. The Company makes safe harbor matching contributions equal to 100% of the first 3% of employees’ eligible earnings which they elect to contribute and an additional 50% on the next 2% of employees’ eligible earnings which they elect to contribute. The Company may also make a

non-elective

contribution, at its discretion. Matching contributions totaled $19 and $48 for the years ended December 31, 2020 and 2019, respectively. The Company made no

non-elective

contributions to the Plan for the years ended December 31, 2020 or 2019.

EQUITY BASED COMPENSATION

9 Months Ended

Sep. 30, 2021

Equity Based Compensation

10.

EQUITY BASED COMPENSATION

In February 2021, Greenidge adopted an equity incentive plan and reserved 3,831,112

shares of class A common stock for issuance under the plan (the “2021 Equity Plan”).

Restricted Common Stock Unit Awards

During the three and nine months ended September 30, 2021, the Company aw

arded 0 and

616,920

restricted common stock units (“RSUs”), respectively, under the 2021 Equity Plan to directors, which are generally eligible to vest over

a three-year period.

The Company’s unvested restricted common stock unit awards activity for the nine months ended September 30, 2021 is summarized below:


	RSUs		Weighted Average Grant Date Fair Value
Unvested at December 31, 2020		—	$	—
Granted		616,920		6.25

Unvested at September 30, 2021		616,920		6.25

The value of RSU grants is measured based on their fair market value on the date of grant and amortized over their requisite service periods. There were no RSU grants during the three months ended September 30, 2021. During the nine months ended September 30, 2021, the fair market value of the awards granted totaled

$3.9

million and as of September 30, 2021, there was approximately

$3.1

million of total unrecognized compensation cost related to unvested restricted stock rights, which is expected to be recognized over a remaining weighted-average vesting period of

approximately 2.4

years.

Common Stock Options

The Company’s stock options activity for the nine months ended September 30, 2021 is summarized below:


	Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding at December 31, 2020		—		$	—		—
Granted		753,968			6.07
Exercised		(160,000	)		6.25
Forfeited		(10,888	)		6.25

Outstanding at September 30, 2020		583,080		$	6.01		9.43	$	11,387
Exercisable as of September 30, 2021		257,484		$	5.80		9.64	$	5,083

The value of common stock option grants is measured based on their fair market value on the date of grant and amortized over their requisite service periods. During the three and nine months ended September 30, 2021, the fair market value of the awards granted totaled $0.1 million and

$1.2

million, respectively. As of September 30, 2021, there was approximately

$0.4

million of total unrecognized compensation cost related to unvested options, which is expected to be recognized over a remaining weighted-average vesting period of

approximately 1.2 years

The weighted average assumptions relating to the valuation of stock options granted for the nine months ended September 30, 2021 were as follows:


Weighted Average fair value of grants	$	1.54
Expected volatility		35	%
Expected term (years)		4.5
Risk-free interest rate		0.4	%
Expected dividend yield		0.0	%

Stock-based Compensation

The Company recognized stock-based compensation expense of

$0.4

millio

and $1.5

million during the three and nine months ended September 30, 2021, respectively. No stock-based compensation expense was recognized during the three and nine months ended September 30, 2020. Stock-based compensation expense is included in selling, general and administrative expenses in the accompanying unaudited condensed interim consolidated statements of operations.

INCOME TAXES

9 Months Ended

Sep. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

11.

INCOME TAXES

The income tax provision for interim periods is determined using an estimate of the annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter, the estimate of the annual effective tax rate is updated, and if the estimated effective tax rate changes, a cumulative adjustment is made.

The effective income tax rate as a percentage of income before income taxes was 38.7% and 48.0% for the three and nine months ended September 30, 2021, respectively. The effective income tax rates for the three and nine months ended September 30, 2021 benefitted from a higher tax bases for the deductibility of the equity-based success fees associated with the Merger. The effective tax rate for the nine months ended September 30, 2021 includes the recognition of a deferred tax liability caused by the reorganization from an LLC to a corporation during the first quarter of 2021. Prior to January 27, 2021, the Company was treated as a partnership for federal and state income tax purposes; therefore, there was no income tax provision or benefit recognized during 2020.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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Commitments and Contingencies Disclosure [Abstract]

EARNINGS PER SHARE

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Earnings Per Share

12.

EARNINGS PER SHARE

The Company calculates basic earnings per share by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. The diluted earnings per share is computed by assuming the exercise, settlement, and vesting of all potential dilutive common stock equivalents outstanding for the period using the treasury stock method.

The following table sets forth a reconciliation of the numerator and denominator used to compute basic earnings and diluted per share of common stock. Basic earnings per share is applicable only for the period from January 29, 2021 through September 30, 2021, which is the period following the reorganization GGH into Greenidge (see Note 2) and presents the period that the Company had outstanding common stock.


$ in thousands, except per share amounts	Three Months Ended September 30, 2021			Nine Months Ended September 30, 2021
Numerator
Net loss	$	(7,896	)	$	(3,099	)
Less: Net income attributable to the member units units before the reorganization		(648	)		(648	)

Net loss attributable to Greenidge	$	(8,544	)	$	(3,747	)
Denominator
Basic weighted average shares outstanding		30,116			28,949
Dilutive effect of equity awards		—			—
Dilutive effect of convertible preferred stock		—			—

Diluted weighted average shares outstanding		30,116			28,949
Loss per share
Basic	$	(0.28	)	$	(0.13	)
Diluted	$	(0.28	)	$	(0.13	)

Prior to the reorganization, there were no shares of common stock outstanding, and the LLC structure of GGH consisted of member units. The Company analyzed the calculation of earnings per unit for periods prior to the reorganization and determined that it resulted in values that would not be meaningful to the users of

these condensed consolidated financial statements. Therefore, earnings per share information has not been presented for the periods during 2020.

For the three and nine months ended September 30, 2021, there was

impact of dilution from any of the outstanding equity awards due to the Net loss, since inclusion of any impact from these awards would be antidilutive.

COMMITMENTS AND CONTINGENCIES

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Commitments and Contingencies

13.

COMMITMENTS AND CONTINGENCIES

Legal Matters

From

time-to-time,

the Company is involved in legal proceedings arising in the ordinary course of business.

Merger-Related Litigation.

After announcement of the Merger, six complaints were file in various U.S. federal district courts by alleged individual stockholders of Support against Support, the individual directors of Support and, in two of the cases, Greenidge and Merger Sub. Of these six complaints, two were filed in the United States District Court for the District of Delaware: Stein v. Support.com, Inc. et al, Case No.

1:21-cv-00650

(May 5, 2021), and Bell v. Support.com, Inc. et al, Case No.

1:21-cv-00672

(May 7, 2021); three were filed in the United States District Court for the Southern District of New York: Broder v. Support.com, Inc. et al, Case No.

1:21-cv-04262

(May 12, 2021), Salerno v. Support.com, Inc. et al, Case No.

1:21-cv-04584

(May 21, 2021), and Bowen v. Support.com, Inc. et al, Case No.

1:21-cv-04797

(May 28, 2021). The sixth lawsuit was filed in the United States District Court for the Eastern District of New York: Steinmetz v. Support.com, Inc. et al, Case No.

1:21-cv-02647

(May 11, 2021). Support and individual members of the Support board were named as defendants in all of the lawsuits; Greenidge and Merger Sub were also named as defendants in Bell and Salerno. The lawsuits generally alleged that Greenidge’s Form

S-4

Registration Statement filed with the U.S. Securities and Exchange Commission in connection with the Merger on May 4, 2021 made misleading omissions of certain material information. The Salerno complaint also alleged that the members of the Support board breached their fiduciary duties in negotiating and approving the Merger Agreement and that Greenidge and Merger Sub aided and abetted that breach. The lawsuits purported to seek to enjoin the Merger, or alternatively, rescission and unspecified damages and costs. On August 2, 2021, lawyers representing a seventh putative stockholder of Support sent a demand letter seeking additional disclosures regarding the proposed transaction and reserving their purported right to seek to enjoin the transaction.

All of the lawsuits have since been voluntarily dismissed by plaintiffs.

Other Matters

Support has received and may in the future receive additional requests for information, including subpoenas, from other governmental agencies relating to the subject matter of a Consent Order and Civil Investigative Demands. The Company intends to cooperate with these information requests and is not aware of any other legal proceedings against the Company by governmental authorities at this time.

Commitments

As of September 30, 2021, the Company had entered into agreements to purchase miner equipment totaling

$142.2

million that required deposits of

$38.5

million. The Company entered into agreements for committed secured financing on this equipment totalin

g $5.2

million that will be funded upon delivery of the miners.

The Company entered into a contract with Empire in September 2020 which provides for the transportation to its pipeline of 15,000 dekatherms of natural gas per day, approximately $158 per month. The contract ends in September 2030 and may be terminated by either party with 12 months’ notice after the initial

10-year

period.

COMMITMENTS AND CONTINGENCIES

From

time-to-time,

the Company is involved in legal proceedings arising in the ordinary course of business. As of the date of the audit report, the Company is not aware of litigation pending against it that could have, individually or in the aggregate, a material adverse effect on its financial position, results of operations, or cash flows.

At December 31, 2020, the Company entered into an agreement to purchase miner equipment totaling $11,910 that required deposits of $5,959. At December 31, 2019, the Company entered into an agreement to purchase miner equipment totaling $7,860 that required deposits of $6,337.

The Company entered into a contract with Empire Pipeline Inc. in September 2020 which provides for the transportation to its pipeline of 15,000 decatherms of natural gas per day, approximately $158 per month. The contract ends in September 2030 and may be terminated by either party with 12 months notice after the initial

10-year

period.

CONCENTRATIONS

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Risks and Uncertainties [Abstract]

Concentrations

14.

CONCENTRATIONS

The Company has one major power customer, NYISO, that accounted for

% and

of its revenue for the three and nine months ended September 30, 2021, respectively, a

and

% for the three and nine months ended September 30, 2020.

% and

100

of accounts receivable were due from this customer at September 30, 2021 and December 31, 2020, respectively.

For cryptocurrency mining, Greenidge considers its mining pool operators to be its customers. Greenidge has historically used a limited number of pool operators that have operated under contracts with a

one-day

term, which allows Greenidge the option to change pool operators at any time. Revenue from one of the Company’s pool operator customers accounted for approximately

% and

% of total revenue for the three and nine months ended September 30, 2021, respectively, and none of the revenue for the three and nine months ended September 30, 2020. Revenue from a different pool operator customer accounted for approximately

% and

% of total revenue for the three and nine months ended September 30, 2021, respectively, and approximately

% and

% of total revenue for the three and nine months ended September 30, 2020, respectively.

The Support Services segment’s largest and second largest customers accounted for approximately

% and

%, respectively, of the Company’s consolidated accounts receivable balance at September 30, 2021.

The Company has one natural gas vendor that accounted for approx

imately

% and

of cost of revenue for the three and nine months ended September 30, 2021, respectively, and approximately

% and

of cost of revenue for the three and nine months ended September 30, 2020, respectively.

CONCENTRATIONS

The Company has one major power customer, the NYISO, that accounts for 35.7% and 90.8% of its revenue for the years ended December 31, 2020 and 2019, respectively. All amounts receivable were due from this customer at December 31, 2020 and 2019.

The Company has one major power vendor that accounted for approximately 56.8% and 55.6% of cost of revenue for the years ended December 31, 2020 and 2019, respectively.

Revenues from Greenidge’s largest pool operator customer comprised approximately 57% of total revenue for the year ended December 31, 2020.

SUPPLEMENTAL CASH FLOW INFORMATION

9 Months Ended

Sep. 30, 2021

Supplemental Cash Flow Information [Abstract]

SUPPLEMENTAL CASH FLOW INFORMATION

15.

SUPPLEMENTAL CASH FLOW INFORMATION

Greenidge had the following noncash investing and financing activities during the nine months ended September 30, 2021:


$ in thousands
Shares issued to Support.com shareholders upon Merger (Notes 3 and 9)	$	93,885
Stock issued to purchase miners	$	991
Contribution of Preferred Units, Senior Priority Units, and notes payable to related party for Greenidge class B common stock (Note 9)	$	72,891
Issuance of shares for investor fee associated with successful completion of Merger (Notes 4 and 9)	$	17,826
Issuance of warrants to advisor in connection with completion of Merger (Note 4 and 9)	$	8,779

OTHER RISKS AND CONSIDERATIONS

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Risks and Uncertainties [Abstract]

Other Risks and Considerations

16.

OTHER RISKS AND CONSIDERATIONS

The United States is presently in the midst of a national health emergency related to a virus, commonly known as Novel Coronavirus

(“COVID-19”).

The overall consequences of

COVID-19

on a national, regional and local level are unknown, but it has the potential to result in a significant economic impact.

COVID-19

did not have a material impact on the Company’s operations during the three and nine months ended September 30, 2021 and 2020. The future impact of this situation on the Company and its results and financial position is not presently determinable.

10.

OTHER RISKS AND CONSIDERATIONS

The United States is presently in the midst of a national health emergency related to a virus, commonly known as Novel Coronavirus

(“COVID-19”).

The overall consequences of

COVID-19

on a national, regional and local level are unknown, but it has the potential to result in a significant economic impact.

COVID-19

did not have a material impact on the Company’s operations during the year ended December 31, 2020. The future impact of this situation on the Company and its results and financial position is not presently determinable.

SUBSEQUENT EVENTS

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Subsequent Events [Abstract]

Subsequent Events

17.

SUBSEQUENT EVENTS

Subsequent events have been evaluated through November 15, 2021, the date at which the condensed consolidated financial statements were available to be issued, and the Company has concluded that no such events or transactions took place that would require disclosure herein except as stated directly below.

Registered Notes Offering

On October 13, 2021, Greenidge completed a registered public offering of $55.2 million of the Company’s 8.50% Senior Notes due 2026 (the “Notes”). The Notes are senior unsecured obligations of the Company and rank equal in

right of payment with the Company’s existing and future senior unsecured indebtedness. The Company received net proceeds after discounts and commissions, but before expenses and payment of the structuring fee, of approximately $53.3 million. The Company intends to use the net proceeds from the offering of the Notes for general corporate purposes, including funding capital expenditures, future acquisitions, investments and working capital and repaying indebtedness.

Purchase of South Carolina Property

In October 2021, a subsidiary of Greenidge entered into a Purchase and Sale Agreement (the “LSC Agreement”) with a subsidiary of LSC Communications, Inc. (the “Seller”), a Delaware corporation, pursuant to which Greenidge has agreed to purchase from the seller two parcels of land containing approximately 175 acres of land located in Spartanburg, South Carolina, including over

750,000

square feet of industrial buildings (the “Property”). As previously disclosed, LSC Communications, Inc. is a portfolio company of private investment funds managed by Atlas Holdings LLC. Greenidge’s controlling shareholder consists of certain funds associated with Atlas Holdings LLC.

The purchase price of the Property is $15.0 million (the “Purchase Price”). Under the terms of the LSC Agreement, Greenidge has deposited $2.5 million in escrow, with such amount to be applied at closing to the Purchase Price. The transaction is expected to close in early December 2021. The LSC Agreement contains customary representations, warranties and covenants of the parties and closing conditions as well as other customary provisions. Greenidge expects to finance the Purchase Price with cash on hand.

Equity Purchase Agreement with B. Riley Principal Capital, LLC

As discussed in Note 9, on September 15, 2021, Greenidge entered into the Purchase Agreement with the Investor pursuant to which Greenidge has the right to “put” or sell to the Investor up to $500 million of shares of class A common stock, subject to certain limitations and conditions set forth in the Purchase Agreement, from time to time during the term of the Purchase Agreement. Following the effectiveness of Greenidge’s registration statement

(File No. 333-259637)

on Form

S-1

on October 6, 2021 relating to the resale of 3,500,000 shares of class A common stock in connection with the Purchase Agreement, the Company began selling shares of class A common stock to the Investor from time to time. Through November

, 2021, Greenidge sold 1,977,500 shares of class A common stock to the Investor for proceeds of approximately $47.9

million, net of discounts.

ERCOT Market Data Centers

In October 2021, we entered into an agreement with a portfolio company of private investment funds managed by Atlas giving us an exclusive right of first refusal at multiple power generation sites comprising over 1,000MW of power generation assets in the ERCOT market. The agreement gives us the exclusive right of first refusal to develop data centers at any current or future power generation sites controlled by the counterparty in the ERCOT market until January 2023. Greenidge’s controlling shareholder consists of certain funds associated with Atlas Holdings LLC.

11.

SUBSEQUENT EVENTS

In January 2021, GC merged into GG and GC was subsequently dissolved.

In January 2021, Greenidge Generation Holdings Inc. (“GGHI”) was formed in the state of Delaware. GGHI has the authority to issue 200,000,000 shares of common stock, $0.0001 par value per share, and 20,000,000 shares of preferred stock, $0.0001 par value per share.

After the formation of GGHI, the equity holders of GGH entered into an asset contribution and exchange agreement in which the holders’ equity interests and outstanding notes payable balances were contributed into GGHI in exchange for 7,000,000 shares of GGHI common stock (28,000,000 shares of GGHI Class B Common Stock after a 4-for-1 stock split that occurred in March 2021).

In January 2021, GGHI completed a private placement offering in which 1,620,000 shares of series A redeemable convertible preferred stock was sold at $25 per share. Total net proceeds from the private placement offering were $37,590.

In February 2021, GGHI adopted an equity incentive plan and reserved 957,778 shares of common stock (3,831,112 shares of Class A Common Stock after a 4-for-1 stock split that occurred in March 2021) for issuance under the plan.

On March 19, 2021, the Company entered into a definitive agreement and plan of merger for a business combination with Support.com, Inc., a Delaware corporation (NASDAQ: SPRT).

On March 19, 2021, the Company and the its largest equity member and its affiliates entered into an arrangement pursuant to which Greenidge agreed, upon request, to direct its bank to issue new letters of credit to replace all or a

portion of the letters of credit provided by the largest equity member and certain of its affiliates, upon the consummation of a potential investment in, financing of, or sale of any assets or equity or debt securities of the Company, which results in net proceeds to the Company of at least $10,000,000.

In May 2021, the Company entered into equipment financing agreements to finance miner equipment purchases totaling $13,947 with a

third-party.

The terms of the financing agreements require interest at 15% per annum. The notes require variable amounts of interest only payments for the first six to eight months of each agreement and variable payments of monthly principal and interest through the maturity date in

October 2023

. The notes are secured by the purchased equipment.

Subsequent events have been evaluated through August 6, 2021, the date at which the consolidated financial statements were available to be issued, and the Company has concluded that no such events or transactions took place that would require disclosure herein except as stated directly above.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Accounting Policies [Abstract]

Basis of Presentation and Use of Estimates

The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).

Basis of Presentation and Principles of Consolidation

The condensed consolidated financial statements include the accounts of Greenidge and its subsidiaries. All significant intercompany accounts and transactions have been eliminated.

Variable Interest Entities

Consolidation of a Variable Interest Entit

On October 2, 2019, Blocker, a related entity through common ownership,

purchased 15,000

preferred units of Greenidge Coin, LLC (“GC”) for

$15,000.

Use of estimates

Significant Accounting Policies

For a detailed discussion about the Company’s significant accounting policies, see the Company’s December 31, 2020 consolidated financial statements.

Cash, Cash Equivalents, and Investments

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its subsidiaries as described in Note 1. All significant intercompany accounts and transactions have been eliminated.

Emissions Expense and Credits

The Company participates in the Regional Greenhouse Gas Initiative (“RGGI”), which requires, by law, that the Company remit credits to

offset 50%

The RGGI credits are recorded on a first in, first out (“FIFO”) basis. The Company incurred emissions expense of $860

tho

and

and $468

tho

usand

for the three and

nine

months ended

September

30, 2021, respectively, and $1,674

usand

and $941

thousand for the three and nine months ended September 30, 2020, respectively, which is

included in power and capacity cost of revenue in the accompanying condensed consolidated statements of operations.

Emissions Expense and Credits

Carbon Offset Credits

Goodwill

Intangible Assets

Asset Retirement Obligations

In accordance with Federal law and ASC

410-20,

Asset Retirement Obligations, the Company recorded an asset retirement obligation

of $2.4

mil

ion

and $2.3

million

at September 30, 2021 and December 31, 2020, respectively. The Company expensed less than

$0.1

million to other income and expense, net during both of the three months ended September 30, 2021 and 2020 for the accretion of interest for the liability and $0.1 during both of the nine

months ended September 30, 2021 and 2020. There were no changes to cash flow estimates related to the coal ash pond asset retirement obligation during the three and

six

months ended September 30, 2021 or 2020. Estimates are based on various assumptions including, but not limited to, closure cost estimates, timing of expenditures, escalation factors, discount rate

of 5.00

and methods for complying with CCR regulations. Additional adjustments to the asset retirement obligations are expected periodically due to potential changes in estimates and assumptions.

Asset Retirement Obligations

The following table reflects the details of the asset retirement obligations included in the consolidated balance sheets at December 31, 2020 and 2019:


	Coal Ash Pond
Balance at January 1, 2019	$	—
Initial recognition		2,135

Balance at December 31, 2019		2,135
Accretion		142

Balance at December 31, 2020	$	2,277

Coal Combustion Residuals

410-20,

Asset Retirement Obligations,

Revenue Recognition

Cryptocurrency Mining Revenue

Fair value of the cryptocurrency award received is determined using the quoted price on Greenidge’s primary exchange of the related cryptocurrency at the time of receipt.

Power and capacity revenue

Services and other revenue

set-up,

security and support, virus and malware removal, wireless network

set-up,

and automation system onboarding and support.

The services described above include four types of offerings:

•

Incident-Based Services—Customers purchase a discrete,

one-time

service. Revenue recognition occurs at the time of service delivery. Fees paid for services sold but not yet delivered are recorded as deferred revenue and recognized at the time of service delivery.

software-as-a-service

(“SaaS”) model under which customers cannot take possession of the technology and pay Support on a

per-user

or usage basis during the term of the arrangement.

Services and other revenue also includes, to a lesser extent, fees for

end-user

software products provided through direct customer downloads and through the sale of these

end-user

30-day

money back guarantee for the majority of its

end-user

software products.

Environmental Trust Liability

The trust is designed

%. In lieu of a trust, the Company has negotiated with its largest equity member to maintain a letter of credit guaranteeing the payment of the liability (see Note

In accordance with ASC

410-20,

Asset Retirement Obligations

, the Company has recorded an environmental liability

$5.0

million

and $4.9

million at September 30, 2021 and December 31, 2020, respectively. The letter of credit related to this liability was for

$5.0

million at September 30, 2021 (see Note 8).

Environmental Trust Liability

410-20,

Asset Retirement Obligations

Leases

On January 1, 2021, the Company adopted ASC 842,

Leases (“ASC 842”)

Right-of-use

In calculating the ROU asset and related lease liability, the Company elected to combine lease and

non-lease

Cryptocurrency Mining Cost of Revenue

Power and Capacity Cost of Revenue

Selling, General, and Administrative Expenses

Selling, general and administrative expenses consist primarily of administrative payroll and benefits, business development costs, professional fees, and insurance.

Stock-Based Compensation

ten years from the date of the grants. These options generally vest on the grant date or over a three year

period

Expected Term

Expected Volatility

– The Company computes stock price volatility over expected terms based on reasonable estimates and comparable public companies as the Company had little trading history of its own common stock.

Risk-Free Interest Rate

– The Company bases the risk-free interest rate on the implied yield available on U.S. Treasury

zero-coupon

issues with an equivalent remaining term.

Expected Dividend

Income Taxes

Earnings Per Share

Accounts Receivable

Cash and Cash Equivalents

Digital Assets

Intangibles—Goodwill and Other

Fuel Deposits

The Company is required to maintain a cash deposit ($100 minimum) with a third-party broker for gas purchases and collection of revenues on the Company’s behalf.

Project Deposit

Miner Equipment Deposits

Property and Equipment

Impairment of Long-Lived Assets

Natural Gas Payable

The Company purchases natural gas through a third-party broker on a daily basis. This amount represents the unpaid balance due to the broker at December 31, 2020 and 2019.

Revenue Recognition

The Company recognizes revenue in accordance with ASC 606,

Revenue from Contracts with Customers

•

Step 1: Identify the contract, or contracts, with the customer;

•

Step 2: Identify the performance obligations in the contract;

•

Step 3: Determine the transaction price;

•

Step 4: Allocate the transaction price to the performance obligations in the contract; and

•

Step 5: Recognize revenue when, or as, the Company satisfies a performance obligation.

If a good or service is not distinct, the good or service is combined with other promised goods or services until a bundle of goods or services is identified that is distinct.

•

Variable consideration;

•

Constraining estimates of variable consideration;

•

The existence of a significant financing component in the contract;

•

Noncash consideration; and

•

Consideration payable to a customer.

Cryptocurrency mining and related activities revenue

Fair value of the cryptocurrency award received is determined using the quoted price on the Company’s primary exchange of the related cryptocurrency at the time of receipt.

There is currently no specific definitive guidance under GAAP or alternative accounting framework for the accounting for cryptocurrencies recognized as revenue or held, and management has exercised significant judgment in determining the appropriate accounting treatment. In the event authoritative guidance is enacted by the Financial Accounting Standards Board (“FASB”), the Company may be required to change its policies, which could have an effect on the Company’s consolidated financial position and results of operations.

Hosting revenue

Hashrate revenue

Power and capacity revenue

Advertising and Promotion Costs

Reclassifications

Certain prior year amounts have been reclassified to conform to the current year’s presentation.

Recent Accounting Pronouncements Not Yet Adopted

In December 2019, the FASB issued ASU

No. 2019-12,

Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU

2019-12”),

which is intended to simplify various aspects related to accounting for income taxes. ASU

2019-12

Recent Accounting Pronouncements Not Yet Adopted

In December 2019, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”)

No. 2019-12,

Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU

2019-12”)

, which is intended to simplify various aspects related to accounting for income taxes. ASU

2019-12

Recent Accounting Pronouncements, Adopted

In February 2016, the FASB issued ASU

No. 2016-02,

Leases (Topic 842), which requires lessees to recognize a

right-of-use

Recent Accounting Pronouncements, Adopted

In May 2014, the FASB issued

ASU 2014-09,

Revenue from Contracts with Customers

Cost of Services and Other Revenue

end-user

software products. Cost of revenue—services and other does not include depreciation and amortization.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Asset Retirement Obligations

The following table reflects the details of the asset retirement obligations included in the consolidated balance sheets at December 31, 2020 and 2019:


	Coal Ash Pond
Balance at January 1, 2019	$	—
Initial recognition		2,135

Balance at December 31, 2019		2,135
Accretion		142

Balance at December 31, 2020	$	2,277

MERGER WITH SUPPORT (Tables)

9 Months Ended

Sep. 30, 2021

Summary of The Estimated Value of The Consideration Paid

The following table summarizes the estimated value of the consideration paid (purchase price):


$ in thousands, except per share amount
Support common stock exchanged		25,745,487
Exchange ratio		0.115

Greenidge Class A common stock exchanged		2,960,731
Greenidge common stock value per share	$	31.71

Consideration paid	$	93,885

Summary of The Preliminary Allocation of The Purchase Price to The Identifiable Assets Acquired and Liabilities


$ in thousands
Cash and cash equivalents	$	27,113
Short-term investments		496
Accounts receivable		5,383
Prepaid expenses and other current assets		713
Property and equipment		1,349
Other long-term assets		383
Accounts payable		(117	)
Accrued expenses and other current liabilities		(3,328	)
Other long-term liabilities		(242	)
Intangible assets		22,690
Deferred tax liability		(6,904	)
Goodwill		46,349

Total consideration	$	93,885

Summary of Identifiable Intangible Assets Determined on a Preliminary Basis

Following is a summary of identifiable intangible assets determined on a preliminary basis and is subject to adjustment during the measurement period, which could be material:


$ in thousands
Identifiable Intangible Asset	Useful Life		Fair Value
Customer relationships		5 years	$	21,600
Tradename		10 years		1,090

Total identifiable intangible assets			$	22,690

Summary of Supplemental Pro Forma Financial Information

The unaudited pro forma financial information reflects certain adjustments related to the acquisition, such as:

•

Conforming the accounting policies of Support to those applied by Greenidge;

•

Recording certain incremental expenses resulting from purchase accounting adjustments, such as amortization expense in connection with fair value adjustments to intangible assets; and

•

Recording the related tax effects of pro forma adjustments.


	Three Months Ended September 30,						Nine Months Ended September 30,
$ in thousands	2021			2020			2021			2020
Revenues	$	42,448		$	16,461		$	87,830		$	47,258
Net (loss) income	$	(11,783	)	$	(1,646	)	$	(12,602	)	$	(6,274	)

MERGER AND OTHER COSTS (Tables)

9 Months Ended

Sep. 30, 2021

Merger and other costs details

The following table provides details of Merger and other costs for the three and nine months ended September 30, 2021:


	Three Months Ended		Nine Months Ended
$ in thousands	September 30, 2021		September 30, 2021
Merger related costs:
Investor fee paid in common stock (Note 9)	$	17,826	$	17,826
Advisor fee paid in warrants (Note 9)		8,779		8,779
Professional and other fees		1,140		1,434

Total Merger related costs		27,745		28,039
Public company filing related costs		2,102		3,056

Total Merger and other costs	$	29,847	$	31,095

SEGMENT INFORMATION (Tables)

9 Months Ended

Sep. 30, 2021

Segment Reporting [Abstract]

Schedule of Information about Reportable Segment

The table below presents information about reportable segments for the three and nine months ended September 30, 2021 and 2020, respectively:


	Three Months Ended September 30,				Nine Months Ended September 30,
$ in thousands	2021		2020		2021		2020
Revenues:
Cryptocurrency Mining and Power Generation	$	34,233	$	6,123	$	61,472	$	13,937
Support Services		1,521		—		1,521		—

Total Revenues	$	35,754	$	6,123	$	62,993	$	13,937

Segment Adjusted EBITDA
Cryptocurrency Mining and Power Generation	$	20,973	$	775	$	33,464	$	1,301
Support Services		204		—		204		—

Total Segments Adjusted EBITDA	$	21,177	$	775	$	33,668	$	1,301

Schedule of Reconciliation of Total of Segments Adjusted EBITDA to Consolidated Loss Before Income Taxes

In addition, the table below provides a reconciliation of the total of the segments Adjusted EBITDA to the consolidated Loss before income taxes:


	Three Months Ended September 30,						Nine Months Ended September 30,
$ in thousands	2021			2020			2021			2020
Total Segments Adjusted EBITDA	$	21,177		$	775		$	33,668		$	1,301
Depreciation and amortization		(2,667	)		(1,064	)		(5,531	)		(3,227	)
Stock-based compensation		(411	)		—			(1,474	)		—
Merger and other costs		(29,847	)		—			(31,095	)		—
Expansion costs		(128	)		—			(128	)		—
Interest expense, net		(1,009	)		—			(1,399	)		(540	)

Consolidated loss before income taxes	$	(12,885	)	$	(289	)	$	(5,959	)	$	(2,466	)

Summary of Reconciliation to Consolidated Total Assets of Company

The table below provides segment assets, which exclude cash and

cash

equivalents and short term investments, and a reconciliation to the consolidated total assets of the Company:


$ in thousands	September 30, 2021
Cryptocurrency Mining and Power Generation		129,802
Support Services		76,864

Total segment assets		206,666
Cash and cash equivalents		51,149
Short term investments		496

Total assets	$	258,311

PROPERTY AND EQUIPMENT (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Summary of Property and Equipment, Net

Property and equipment, net consisted of the following at September 30, 2021 and December 31, 2020:


$ in thousands	Estimated Useful Lives		September 30, 2021			December 31, 2020
Plant infrastructure		15 - 39 years	$	34,273		$	33,944
Miners		5 years		36,779			10,236
Miner facility infrastructure		15 years		14,787			8,791
Land		N/A		300			300
Equipment		5 years		948			211
Software		3 years		1,130			66
Coal ash impoundment		4 years		2,135			2,135
Construction in process		N/A		6,869			3,989
Miner deposits		N/A		38,467			5,959

				135,688			65,631
Less: Accumulated depreciation				(14,156	)		(8,986	)

			$	121,532		$	56,645

Property and equipment, net consisted of the following at December 31:


	Estimated Useful Lives		2020			2019
Plant infrastructure		15 – 39 years	$	33,944		$	31,387
Miners		5 years	$	10,236			—
Miner Facility		15 years		8,791			—
Land		N/A		300			300
Equipment		5 years		211			206
Software		3 years		66			66
Coal ash impoundment		4 years		2,135			2,135
Construction in process		N/A		3,989			7,392

				59,672			41,486
Less: Accumulated depreciation				(8,986	)		(4,422	)

			$	50,686		$	37,064

NOTES PAYABLE (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Debt Disclosure [Abstract]

Summary of Notes Payable

The following table provides information on the equipment financing agreements:


$ in thousands
					Interest Rate			Initial Financing		Balance as of:
Note	Loan Date		Maturity Date		Interest Rate			Initial Financing		September 30, 2021			December 31, 2020
A		December 2020		June 2022		17.0	%	$	4,482	$	1,992		$	4,233
B		December 2020		June 2022		17.0	%		428		166			404
C		March 2021		November 2022		17.0	%		2,229		1,733			—
D		April 2021		December 2022		17.0	%		4,012		3,343			—
E—H		May 2021		October 2023		15.0	%		12,080		11,751			—
I		July 2021		January 2023		17.0	%		4,457		3,962			—
J		July 2021		March 2023		17.0	%		2,701		2,415			—

											25,363			4,637
Less: Current portion											(17,994	)		(3,273	)

										$	7,369		$	1,364

As of December 31, 2019, there were no notes payable outstanding. Notes payable consisted of the following at December 31, 2020:


Miner equipment note A	$	4,233
Miner equipment note B		404

		4,637
Less: Current portion		(3,273	)

	$	1,364

Summary of Future Maturities of Notes Payable

Future maturities of notes payable are as follows for the years ending December 31:


2021	$	3,273
2022		1,364

	$	4,637

RELATED PARTY TRANSACTIONS (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of notes payable to related party

Notes payable to related party consisted of the following:


$ in thousands	September 30, 2021		December 31, 2020
Note payable to a related party due June 2021	$	—	$	2,382
Note payable to a related party due May 2021		—		1,191

	$	—	$	3,573
Less: Current Portion	$	—	$	(3,573	)

	$	—	$	—

Notes payable to related party consisted of the following at December 31:


	2020			2019
Note payable to a related party with interest at 8% per annum. All outstanding principal and accrued but unpaid interest is due June 2021.	$	2,382		$	—
Note payable to a related party with interest at 8% per annum. All outstanding principal and accrued but unpaid interest is due May 2021.		1,191			—
Notes payable converted into Senior Priority Units—Tranche 1 (see Note 6).		—			12,700

		3,573			12,700
Less: Current portion		(3,573	)		(5,000	)

	$	—		$	7,700

EQUITY BASED COMPENSATION (Tables)

9 Months Ended

Sep. 30, 2021

Share-based Payment Arrangement [Abstract]

Schedule of unvested restricted common stock unit awards activity

The Company’s unvested restricted common stock unit awards activity for the nine months ended September 30, 2021 is summarized below:


	RSUs		Weighted Average Grant Date Fair Value
Unvested at December 31, 2020		—	$	—
Granted		616,920		6.25

Unvested at September 30, 2021		616,920		6.25

Schedule of stock options activity

The Company’s stock options activity for the nine months ended September 30, 2021 is summarized below:


	Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding at December 31, 2020		—		$	—		—
Granted		753,968			6.07
Exercised		(160,000	)		6.25
Forfeited		(10,888	)		6.25

Outstanding at September 30, 2020		583,080		$	6.01		9.43	$	11,387
Exercisable as of September 30, 2021		257,484		$	5.80		9.64	$	5,083

Schedule of weighted average assumptions relating to the valuation of stock options

The weighted average assumptions relating to the valuation of stock options granted for the nine months ended September 30, 2021 were as follows:


Weighted Average fair value of grants	$	1.54
Expected volatility		35	%
Expected term (years)		4.5
Risk-free interest rate		0.4	%
Expected dividend yield		0.0	%

EARNINGS PER SHARE (Tables)

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Schedule of basic earnings and diluted per share of common stock


$ in thousands, except per share amounts	Three Months Ended September 30, 2021			Nine Months Ended September 30, 2021
Numerator
Net loss	$	(7,896	)	$	(3,099	)
Less: Net income attributable to the member units units before the reorganization		(648	)		(648	)

Net loss attributable to Greenidge	$	(8,544	)	$	(3,747	)
Denominator
Basic weighted average shares outstanding		30,116			28,949
Dilutive effect of equity awards		—			—
Dilutive effect of convertible preferred stock		—			—

Diluted weighted average shares outstanding		30,116			28,949
Loss per share
Basic	$	(0.28	)	$	(0.13	)
Diluted	$	(0.28	)	$	(0.13	)

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)

9 Months Ended

Sep. 30, 2021

Supplemental Cash Flow Elements [Abstract]

Summary of noncash investing and financing activities

Greenidge had the following noncash investing and financing activities during the nine months ended September 30, 2021:


$ in thousands
Shares issued to Support.com shareholders upon Merger (Notes 3 and 9)	$	93,885
Stock issued to purchase miners	$	991
Contribution of Preferred Units, Senior Priority Units, and notes payable to related party for Greenidge class B common stock (Note 9)	$	72,891
Issuance of shares for investor fee associated with successful completion of Merger (Notes 4 and 9)	$	17,826
Issuance of warrants to advisor in connection with completion of Merger (Note 4 and 9)	$	8,779

ORGANIZATION AND DESCRIPTION OF BUSINESS - Additional Information (Detail) - Greenidge Blocker Corp [Member] - USD ($) $ in Thousands	Jul. 01, 2020	Oct. 02, 2019
Preferred unit, issued		15,000
Preferred unit, issuance value	$ 16,300	$ 15,000

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of Asset Retirement Obligations (Detail) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Asset Retirement Obligation Disclosure [Abstract]
Beginning Balance	$ 2,277	$ 2,135	$ 2,135	$ 0
Initial recognition				2,135
Accretion	103	$ 108	142
Ending Balance	$ 2,400		$ 2,277	$ 2,135

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Detail)		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 11, 2021 USD ($)	Jan. 31, 2021 shares	Sep. 30, 2021 USD ($) Bitcoins	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Bitcoins	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Bitcoins	Dec. 31, 2019 USD ($) Bitcoins	Jul. 01, 2020 USD ($)	Oct. 02, 2019 USD ($) shares	Dec. 31, 2018 USD ($)
Accounts receivable write off as uncollectible							$ 0	$ 0
Impairment Loss								100,000
Cash deposit							100,000
Deposit Contracts, Assets							$ 74,000	510,000
Percentage of annual emission expense and credit in the following year			50.00%		50.00%		50.00%
Asset retirement obligation			$ 2,400,000		$ 2,400,000		$ 2,277,000	2,135,000			$ 0
Discount rate on asset retirement obligations			5.00%		5.00%		5.00%
Discount rate on environmental trust liability during current period			4.50%		4.50%		4.50%
Environmental trust liability			$ 4,994,000		$ 4,994,000		$ 4,927,000	4,697,000
Provision for income taxes			$ (4,989,000)	$ 0	(2,860,000)	$ 0	0	0
Advertising and promotional costs							117,000	$ 0
Asset retirement obligation expense					$ 103,000	108,000	$ 142,000
Share based compensation arrangement,expiration period					10 years
Vesting period					3 years
Number of digital assets \| Bitcoins			29.8		29.8		26.1	38.9
Right-of-use assets, net			$ 1,369,000		$ 1,369,000		$ 0
Equipment [Member]
Right-of-use assets, net	$ 1,400,000
Finance lease obligation	$ 1,200,000
Lease end date	Aug. 31, 2022
Greenidge Blocker Corp [Member]
Preferred unit, issued \| shares										15,000
Preferred unit, issuance value									$ 16,300,000	$ 15,000,000
Impairment Of Long Lived Assets
Impairment Loss							0	$ 0
Digital Assets
Impairment Loss							$ 100,000
Hash Rate Revenue [Member] \| Maximum [Member]
Revenue term period							180 days
Hash Rate Revenue [Member] \| Minimum [Member]
Revenue term period							30 days
Letter of Credit [Member]
Long-term Line of Credit			5,000.0		5,000.0		$ 4,938,000	4,938,000
GGHI Class B Common Stock [Member]
Shares issued in exchange for acquisition of ownership interests \| shares		28,000,000
Cost of Sales [Member]
Emissions expense			860,000	$ 1,674,000	468,000	$ 941,000	$ 1,738,000	$ 206,000
Purchase of voluntary carbon offset credits					$ 700,000
Other Income And Expense [Member]
Asset retirement obligation expense			$ 100

MERGER WITH SUPPORT - Summary of The Estimated Value of The Consideration Paid (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 13, 2021 $ / shares	Dec. 31, 2020 $ / shares
Business Acquisition [Line Items]
Common stock, Par value	$ 0.0001		$ 0.0001
Greenidge Generation Holdings Inc [Member]
Business Acquisition [Line Items]
Common stock exchanged amount \| shares	25,745,487
Right to receive common stock exchange ratio	0.115
Common stock, Par value	$ 31.71
Consideration paid \| $	$ 93,885
Common Class A [Member]
Business Acquisition [Line Items]
Right to receive common stock exchange ratio	0.115
Common stock, Par value	$ 0.0001	$ 0.0001
Consideration paid \| $	$ 93,900
Common Class A [Member] \| Greenidge Generation Holdings Inc [Member]
Business Acquisition [Line Items]
Common stock exchanged amount \| shares	2,960,731

MERGER WITH SUPPORT - Summary of The Preliminary Allocation of The Purchase Price to The Identifiable Assets Acquired and (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Business Combinations [Abstract]
Cash and cash equivalents	$ 27,113
Short-term investments	496
Accounts receivable	5,383
Prepaid expenses and other current assets	713
Property and equipment	1,349
Other long-term assets	383
Accounts payable	(117)
Accrued expenses and other current liabilities	(3,328)
Other long-term liabilities	(242)
Intangible assets	22,690
Deferred tax liability	(6,904)
Goodwill	46,349	$ 0
Total consideration	$ 93,885

MERGER WITH SUPPORT - Summary of Identifiable Intangible Assets Determined on a Preliminary Basis (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Business Acquisition [Line Items]
Fair value of intangible assets	$ 22,690
Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated useful life	5 years
Fair value of intangible assets	$ 21,600
Trade Names [Member]
Business Acquisition [Line Items]
Estimated useful life	10 years
Fair value of intangible assets	$ 1,090

MERGER WITH SUPPORT - Summary of Supplemental Pro Forma Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Net (loss) income	$ (7,896)	$ (289)	$ 4,797	$ (2,177)	$ (3,099)	$ (2,466)	$ (3,290)	$ (8,475)
Greenidge Generation Holdings Inc [Member]
Business Acquisition [Line Items]
Revenues	42,448	16,461			87,830	47,258
Net (loss) income	$ (11,783)	$ (1,646)			$ (12,602)	$ (6,274)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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MERGER WITH SUPPORT - Additional Information (Details) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares	Sep. 30, 2021 USD ($) d $ / shares	Sep. 13, 2021 $ / shares	Dec. 31, 2020 $ / shares
Business Acquisition [Line Items]
Common stock, Par value \| $ / shares	$ 0.0001	$ 0.0001		$ 0.0001
Amortization expense		$ 200
Business acquisition proforma costs	$ 30,000	32,400
Transaction costs after tax		$ 26,900
Common Class A [Member]
Business Acquisition [Line Items]
Common stock, Par value \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001
Right to receive common stock exchange ratio	0.115	0.115
Consideration paid	$ 93,900	$ 93,900
Greenidge Generation Holdings Inc [Member]
Business Acquisition [Line Items]
Common stock, Par value \| $ / shares	$ 31.71	$ 31.71
Right to receive common stock exchange ratio	0.115	0.115
Trading days \| d		10
Consideration paid	$ 93,885	$ 93,885
Revenue	1,500	$ 1,500
Transaction costs after tax	$ 24,500

MERGER AND OTHER COSTS - Details of Merger and Other Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Merger Related Costs [Abstract]
Investor fee paid in common stock (Note 9) shares	$ 17,826		$ 17,826
Advisor fee paid in warrants (Note 9)	8,779		8,779
Professional and other fees	1,140		1,434
Total Merger related costs	27,745		28,039
Public company filing related costs	2,102		3,056
Total Merger and other costs	$ 29,847	$ 0	$ 31,095	$ 0

SEGMENT INFORMATION - Additional Information (Details)	9 Months Ended
SEGMENT INFORMATION - Additional Information (Details)	Sep. 30, 2021 Segment
Segment Reporting [Abstract]
Number of operating segments	2
Number of reportable segment	2

SEGMENT INFORMATION - Schedule of Information about Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total revenue	$ 35,754	$ 6,123	$ 62,993	$ 13,937	$ 20,114	$ 4,439
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	35,754	6,123	62,993	13,937
Total Segments Adjusted EBITDA	21,177	775	33,668	1,301
Cryptocurrency Mining [Member]
Segment Reporting Information [Line Items]
Total revenue	31,156	3,043	54,217	8,673	$ 13,016	$ 410
Cryptocurrency Mining [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenue	34,233	6,123	61,472	13,937
Total Segments Adjusted EBITDA	20,973	775	33,464	1,301
Support Services [Member]
Segment Reporting Information [Line Items]
Total revenue	1,521		1,521
Support Services [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Segments Adjusted EBITDA	$ 204		$ 204

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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SEGMENT INFORMATION - Schedule of Reconciliation of Total of Segments Adjusted EBITDA to Consolidated Loss Before Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Merger and other costs	$ 29,847	$ 0	$ 31,095	$ 0
Interest expense, net	1,009	0	1,377	0	$ 91
Consolidated loss before income taxes	(12,885)	(289)	(5,959)	(2,466)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Segments Adjusted EBITDA	21,177	775	33,668	1,301
Depreciation and amortization	(2,667)	(1,064)	(5,531)	(3,227)
Stock-based compensation	(411)		(1,474)
Merger and other costs	(29,847)		(31,095)
Expansion costs	(128)		(128)
Interest expense, net	(1,009)		(1,399)	(540)
Consolidated loss before income taxes	$ (12,885)	$ (289)	$ (5,959)	$ (2,466)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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SEGMENT INFORMATION - Summary of Reconciliation to Consolidated Total Assets of Company (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	$ 51,149	$ 5,052	$ 3,236	$ 11,750	$ 705
Short term investments	496	0
Total assets	258,311	$ 64,567		$ 56,844
Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	206,666
Cryptocurrency Mining [Member] \| Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	129,802
Support Services [Member] \| Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 76,864

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442526-122756

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=123419778&loc=d3e5710-111685

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-URI http://asc.fasb.org/extlink&oid=124359900&loc=SL124442552-122756

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 25
-Subparagraph (a)
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 32
-Subparagraph (d)
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-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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-Paragraph 30
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

PROPERTY AND EQUIPMENT - Summary of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross		$ 59,672	$ 41,486
Property, Plant and Equipment, Gross	$ 135,688	65,631
Less: Accumulated depreciation	(14,156)	(8,986)	(4,422)
Total		50,686	37,064
Property and equipment, net	121,532	56,645
Plant infrastructure [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 34,273	$ 33,944	31,387
Plant infrastructure [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	15 years	15 years
Plant infrastructure [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	39 years	39 years
Miners [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 36,779	$ 10,236
Estimated Useful Lives	5 years	5 years
Miner facility infrastructure [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 14,787	$ 8,791
Estimated Useful Lives	15 years	15 years
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 300	$ 300	300
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 948	$ 211	206
Estimated Useful Lives	5 years	5 years
Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 1,130	$ 66	66
Estimated Useful Lives	3 years	3 years
Coal ash impoundment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 2,135	$ 2,135	2,135
Estimated Useful Lives	4 years	4 years
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 6,869	$ 3,989	$ 7,392
Miner deposits [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 38,467	$ 5,959

PROPERTY AND EQUIPMENT - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2,700	$ 1,100	$ 5,500	$ 3,200	$ 4,564	$ 1,679

NOTES PAYABLE - Summary of Notes Payable (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Less: Current portion	$ (17,994)	$ (3,273)	$ 0
Total	7,369	1,364	$ 0
Equipment Finance Agreement [Member]
Notes Payable	25,363	4,637
Less: Current portion	(17,994)	(3,273)
Total	7,369	1,364
Miner Equipment Note A [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 1,992	$ 4,233
Loan Date	December 2020
Maturity Date	June 2022	July 2022
Interest Rate	17.00%	17.00%
Initial Financing	$ 4,482	$ 4,482
Miner Equipment Note B [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 166	$ 404
Loan Date	December 2020
Maturity Date	June 2022	June 2022
Interest Rate	17.00%	17.00%
Initial Financing	$ 428	$ 428
Miner Equipment Note C [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 1,733
Loan Date	March 2021
Maturity Date	November 2022
Interest Rate	17.00%
Initial Financing	$ 2,229
Miner Equipment Note D [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 3,343
Loan Date	April 2021
Maturity Date	December 2022
Interest Rate	17.00%
Initial Financing	$ 4,012
Miner Equipment Note E And H [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 11,751
Loan Date	May 2021
Maturity Date	October 2023
Interest Rate	15.00%
Initial Financing	$ 12,080
Miner Equipment Note I [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 3,962
Loan Date	July 2021
Maturity Date	January 2023
Interest Rate	17.00%
Initial Financing	$ 4,457
Miner Equipment Note J [Member] \| Equipment Finance Agreement [Member]
Notes Payable	$ 2,415
Loan Date	July 2021
Maturity Date	March 2023
Interest Rate	17.00%
Initial Financing	$ 2,701

NOTES PAYABLE - Summary of Future Maturities of Notes Payable (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Maturities of Long-term Debt [Abstract]
2021	$ 3,273
2022	1,364
Total	$ 4,637

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

NOTES PAYABLE - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Principal borrowings			$ 4,637
Notes Payable [Member]
Interest expense	$ 1,000	$ 1,400	91
Equipment Finance Agreement [Member]
Principal borrowings			10,698
Equipment Finance Agreement [Member] \| Miner Equipment Note A [Member]
Debt instrument, face amount	$ 4,482	$ 4,482	$ 4,482
Interest rate per annum	17.00%	17.00%	17.00%
Risk premium fee			$ 482
Principal payments			222
Risk premium payments			$ 27
Maturity date		June 2022	July 2022
Equipment Finance Agreement [Member] \| Miner Equipment Note B [Member]
Debt instrument, face amount	$ 428	$ 428	$ 428
Interest rate per annum	17.00%	17.00%	17.00%
Principal payments			$ 24
Maturity date		June 2022	June 2022

RELATED PARTY TRANSACTIONS - Additional Information (Detail) - USD ($)			9 Months Ended	12 Months Ended
	Mar. 19, 2021	Jul. 01, 2020	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 02, 2019
Related Party Transaction [Line Items]
Related party loan outstanding balance			$ 0	$ 3,573,000	$ 12,700,000
Notes Payable Interest Rate At 8 With Due June 2021 [Member]
Related Party Transaction [Line Items]
Related party loan outstanding balance			0	2,382,000	0
Notes Payable Interest Rate At 8 With Due May 2021 [Member]
Related Party Transaction [Line Items]
Related party loan outstanding balance			0	1,191,000	0
Greenidge Blocker Corp [Member]
Related Party Transaction [Line Items]
Preferred unit, issued						15,000
Preferred unit, issuance value		$ 16,300,000				$ 15,000,000
Letter of Credit [Member]
Related Party Transaction [Line Items]
Net proceeds from new line of credit	$ 10,000
Line of credit			5,000.0	4,938,000	4,938,000
Letter of Credit [Member] \| Empire Pipeline Incorporated [Member]
Related Party Transaction [Line Items]
Repayments of lines of credit			3,600
Line of credit				3,630,000	3,630,000
Atlas [Member]
Related Party Transaction [Line Items]
Partners capital account, Acquisitions		$ 16,277,000
Limited guaranty payment			1,000,000.0
Exposure under guarantee			0
Atlas [Member] \| Letter of Credit [Member]
Related Party Transaction [Line Items]
Repayments of lines of credit				184,000	$ 206,000
Promissory Note Agreement [Member]
Related Party Transaction [Line Items]
Interest expense			$ 500,000	$ 20,000
Promissory Note Agreement [Member] \| Atlas [Member]
Related Party Transaction [Line Items]
Debt instrument, interest rate, stated percentage			8.00%	8.00%	8.00%
Interest expense				$ 553,000	$ 673,000
Promissory Note Agreement [Member] \| Atlas [Member] \| Notes Payable Interest Rate At 8 With Due June 2021 [Member]
Related Party Transaction [Line Items]
Maturity date				June 2021
Related party loan outstanding balance				$ 2,400
Promissory Note Agreement [Member] \| Atlas [Member] \| Notes Payable Interest Rate At 8 With Due May 2021 [Member]
Related Party Transaction [Line Items]
Maturity date				May 2021
Related party loan outstanding balance				$ 1,200

RELATED PARTY TRANSACTIONS - Summary of Notes Payable to Related Party (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Notes payable	$ 0	$ 3,573	$ 12,700
Less: Current Portion	0	(3,573)	(5,000)
Notes payable to related party	0	0	7,700
Note payable to a related party due June 2021 [Member]
Debt Instrument [Line Items]
Notes payable	0	2,382	0
Note payable to a related party due May 2021 [Member]
Debt Instrument [Line Items]
Notes payable	$ 0	1,191	0
Notes payable converted into Senior Priority Units—Tranche 1 [Member]
Debt Instrument [Line Items]
Notes payable		$ 0	$ 12,700

STOCKHOLDERS' EQUITY - Additional Information (Detail)		1 Months Ended		3 Months Ended			6 Months Ended		9 Months Ended		12 Months Ended
STOCKHOLDERS' EQUITY - Additional Information (Detail)	Sep. 15, 2021 USD ($)	Jan. 31, 2021 USD ($) shares	Oct. 31, 2018 shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Tranches $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares	Sep. 13, 2021 $ / shares shares	Jan. 01, 2021 $ / shares
Class of Stock [Line Items]
Capital units, authorized														2,400,000,000
Common stock, shares authorized				3,000,000,000					3,000,000,000		0
Common stock, par or stated value per share \| $ / shares				$ 0.0001					$ 0.0001		$ 0.0001
Preferred stock, shares authorized				20,000,000					20,000,000		0			20,000,000
Preferred stock, par or stated value per share \| $ / shares				$ 0.0001					$ 0.0001		$ 0.0001			$ 0.0001
Shares issued, Price per share \| $ / shares				$ 31.71					$ 31.71
Common stock, shares issued				38,667,705					38,667,705		0
Common stock, shares outstanding				38,667,705					38,667,705		0
Common units, voting rights											Common unit holders are entitled to one vote per common unit, except for such votes or consents that are reserved solely for the holders of preferred units
Shares based compensation, expenses \| $				$ 0.4	$ 0				$ 1.5	$ 0
Common units, issued											750	750
Common units, outstanding											750	750
Preferred units, voting rights											Preferred unit holders are entitled to one vote per preferred unit
Number of tranche \| Tranches											2
Partners capital account, exchange and conversions \| $											$ 13,926,000
Senior priority units, voting rights									Senior Priority Units had no voting rights.		Senior Priority Units have no voting rights
Preferred Stock Shares Outstanding				0					0		0
Common Stock Value \| $				$ 4,000					$ 4,000		$ 0
Payments Of Stock Issuance Costs \| $									$ 2,296,000	$ 0
Shares Issued Price Per Share \| $ / shares				$ 31.71					$ 31.71
Greenidge Generation Holdings Inc Member [Member]
Class of Stock [Line Items]
Preferred units, voting rights									one vote per preferred unit
Maximum [Member]
Class of Stock [Line Items]
Maximum Class a Common Stock and class b Common Stock Shares In Excess of the Exchange Cap	19.99%
Common Stock
Class of Stock [Line Items]
Common units, voting rights											Common unit holders are entitled to one vote per common unit, except for such votes or consents that are reserved solely for the holders of preferred units.
Resticted Common Stock Unit
Class of Stock [Line Items]
Shares based payment arrangement, equity instrument other than option, grants in period									616,920
Shares based payment arrangement, equity instrument other than option, non vested units				616,920					616,920		0
Equity Incentive Plan
Class of Stock [Line Items]
Shares based payment arrangement, equity instrument other than option, grants in period			750
Shares based payment arrangement, vesting rights percentage											100.00%
Equity Incentive Plan \| Resticted Common Stock Unit
Class of Stock [Line Items]
Shares based payment arrangement, equity instrument other than option, grants in period													750
Shares based payment arrangement, equity instrument other than option, vested in period											730	600
Shares based payment arrangement, equity instrument other than option, non vested units											20	150
Shares based compensation, expenses \| $				$ 0		$ 0	$ 0	$ 0			$ 0	$ 0
Greenidge Common Stock
Class of Stock [Line Items]
Number of shares after split		(28,000,000)
Stockholders equity note stock split		4-for-1
Limited Liability Company LLC Common Units \| Equity Incentive Plan
Class of Stock [Line Items]
Shares based payment arrangement, shares purchased for award			1,250
Limited Liability Company LLC Senior Priority Unit \| Tranche One
Class of Stock [Line Items]
Partners capital account, exchange and conversions \| $									$ 13.9		13,926,000
Limited Liability Company LLC Senior Priority Unit \| Tranche Two
Class of Stock [Line Items]
Partners capital account, acquisitions \| $									$ 16.3		$ 16,276,000
Private Placement
Class of Stock [Line Items]
Proceeds from issuance of private placement \| $		$ 37,100,000
Private Placement \| Common Stock Purchase Agreement and Registration Rights Agreement [Member] \| Greenidge Generation Holdings Inc Member [Member]
Class of Stock [Line Items]
Proceeds from common stock purchase agreement \| $	$ 200,000,000
Private Placement \| Common Stock Purchase Agreement and Registration Rights Agreement [Member] \| Maximum [Member] \| Greenidge Generation Holdings Inc Member [Member]
Class of Stock [Line Items]
Discount Rate	6.00%
Private Placement \| Common Stock Purchase Agreement and Registration Rights Agreement [Member] \| Minimum Member \| Greenidge Generation Holdings Inc Member [Member]
Class of Stock [Line Items]
Discount Rate	5.00%
Common Class A
Class of Stock [Line Items]
Common stock, par or stated value per share \| $ / shares				$ 0.0001					$ 0.0001					$ 0.0001
Common stock, shares issued				9,627,705					9,627,705
Common stock, shares outstanding				9,627,705					9,627,705
Stock issued during period shares, Conversion of convertible securities									5,760,000
Additional Common Stock Shares Issued									562,174
Additional Common Stock Value Issued \| $				$ 17,800,000					$ 17,800,000
Stock Owned Percentage									16.60%
Warrant to Purchase of Common Stock									344,800
Class of Warrant or Right Exercise Price of Warrants or Rights1 \| $ / shares				$ 6.25					$ 6.25
Proceeds from Issuance of warrants \| $									$ 8,800,000
Common Class A \| Maximum [Member]
Class of Stock [Line Items]
Investors obligation to purchase own issued and outstanding shares	4.99%
Common Class A \| Merger Agreements
Class of Stock [Line Items]
Common stock, shares issued				2,960,731					2,960,731
Common Stock Value \| $				$ 93,900,000					$ 93,900,000
Payments Of Stock Issuance Costs \| $									$ 91,600,000
Common Class A \| Common Stock Purchase Agreement and Registration Rights Agreement [Member]
Class of Stock [Line Items]
Proceeds from issuance of private placement \| $	$ 500,000,000
Common Class B
Class of Stock [Line Items]
Common stock, shares authorized														600,000,000
Common stock, par or stated value per share \| $ / shares														$ 0.0001
Common Stock, voting rights		ten votes
Common stock, shares issued				29,040,000					29,040,000
Common stock, shares outstanding				29,040,000					29,040,000
Stock issued during period shares, Conversion of convertible securities									720,000
Series A Redeemable Convertible Preferred Stock \| Private Placement
Class of Stock [Line Items]
Stock issued during period, Shares		1,620,000
Shares issued, Price per share \| $ / shares															$ 25
Shares Issued Price Per Share \| $ / shares															$ 25
GGHI Class B Common Stock
Class of Stock [Line Items]
Shares issued in exchange for acquisition of ownership interests		28,000,000
GGHI Class B Common Stock \| Greenidge Common Stock
Class of Stock [Line Items]
Shares issued in exchange for acquisition of ownership interests		7,000,000
GGHI Class A Common Stock \| Common Stock
Class of Stock [Line Items]
Common Stock, voting rights									one vote per share

MEMBERS' EQUITY - Additional Information (Detail)	1 Months Ended	3 Months Ended			6 Months Ended		9 Months Ended		12 Months Ended
MEMBERS' EQUITY - Additional Information (Detail)	Oct. 31, 2018 shares	Sep. 30, 2021 USD ($) shares	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) Tranches $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares
Common units, Authorized									1,250
Preferred units, Authorized									39,228
Senior priority units units, Authorized									10,000
Common units, Voting rights									Common unit holders are entitled to one vote per common unit, except for such votes or consents that are reserved solely for the holders of preferred units
Shares based compensation, Expenses \| $		$ 0.4	$ 0				$ 1.5	$ 0
Common units, Issued									750	750
Common units, Outstanding									750	750
Preferred units, Voting rights									Preferred unit holders are entitled to one vote per preferred unit
Preferred units, Liquidation preference per unit \| $ / shares									$ 1
Number of tranche \| Tranches									2
Partners capital account, Exchange and conversions \| $									$ 13,926,000
Senior priority units, Voting rights							Senior Priority Units had no voting rights.		Senior Priority Units have no voting rights
Cumulatively accrued rate of return on the investment									8.00%
Senior priority units, Liquidation preference value \| $									$ 14,498,000
Limited Liability Company LLC Senior Priority Unit [Member] \| Tranche One [Member]
Partners capital account, Exchange and conversions \| $							$ 13.9		13,926,000
Limited Liability Company LLC Senior Priority Unit [Member] \| Tranche Two [Member]
Partners capital account, Acquisitions \| $							$ 16.3		$ 16,276,000
Restricted Stock Units (RSUs) [Member]
Shares based payment arrangement, Equity instrument other than option, Grants in period							616,920
Shares based payment arrangement, Equity instrument other than option, Non vested units		616,920					616,920		0
Equity Incentive Plan [Member]
Shares based payment arrangement, Equity instrument other than option, Grants in period	750
Shares based payment arrangement, Vesting rights percentage									100.00%
Equity Incentive Plan [Member] \| Limited Liability Company LLC Common Units [Member]
Shares based payment arrangement, Shares purchased for award	1,250
Equity Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Shares based payment arrangement, Equity instrument other than option, Grants in period											750
Shares based payment arrangement, Equity instrument other than option, Vested in period									730	600
Shares based payment arrangement, Equity instrument other than option, Non vested units									20	150
Shares based compensation, Expenses \| $		$ 0		$ 0	$ 0	$ 0			$ 0	$ 0

EMPLOYEE BENEFIT PLAN - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Matching contributions recognized as expense	$ 19	$ 48
Non elective contributions to the plan	$ 0	$ 0
First Salary Deferral Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percent of match	100.00%
Employer matching contribution percent of employees gross pay	3.00%
Second Salary Deferral Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percent of match	50.00%
Employer matching contribution percent of employees gross pay	2.00%

EQUITY BASED COMPENSATION - Schedule of Unvested Restricted Common Stock Unit Awards Activity (Detail)	9 Months Ended
	Sep. 30, 2021 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	$ 1.54
Resctricted Common Stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at December 31, 2020 \| shares	0
Granted \| shares	616,920
Unvested at September 30, 2021 \| shares	616,920
Unvested at December 31, 2020	$ 0
Granted	6.25
Unvested at September 30, 2021	$ 6.25

EQUITY BASED COMPENSATION - Schedule of Stock Options Activity (Detail) - Common Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at December 31, 2020		0
Granted		753,968
Exercised		(160,000)
Forfeited		(10,888)
Outstanding at September 30, 2020		583,080
Options vested and exercisable as of June 30, 2021	257,484
Outstanding at December 31, 2020		$ 0
Granted		6.07
Exercised		6.25
Forfeited		6.25
Outstanding at September 30, 2020		$ 6.01
Options vested and exercisable as of September 30, 2021	$ 5.80
Weighted Average Remaining Contractual Life (in years)		9 years 5 months 4 days
Options vested and exercisable as of September 30, 2021	9 years 7 months 20 days
Aggregate Intrinsic Value		$ 11,387
Options vested and exercisable as of September 30, 2021	$ 5,083

EQUITY BASED COMPENSATION - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Feb. 28, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Line Items]
Vesting period			3 years
Stock-based compensation expense	$ 0.4	$ 0	$ 1.5	$ 0
2021 Equity Plan [Member]
Disclosure Of Compensation Related Costs Sharebased Payments [Line Items]
Common stock reserved for issuance					3,831,112
Resticted Common Stock Unit
Disclosure Of Compensation Related Costs Sharebased Payments [Line Items]
Number of shares, granted			616,920
Fair market value of the awards granted			$ 3.9
Unrecognized compensation cost	$ 3.1		$ 3.1
Weighted average vesting period			2 years 4 months 24 days
Resticted Common Stock Unit \| 2021 Equity Plan [Member]
Disclosure Of Compensation Related Costs Sharebased Payments [Line Items]
Number of shares, granted	0		616,920
Vesting period			3 years
Common Stock Options [Member]
Disclosure Of Compensation Related Costs Sharebased Payments [Line Items]
Unrecognized compensation cost	$ 0.4		$ 0.4
Weighted average vesting period			1 year 2 months 12 days
Fair market value of award, Options granted			$ 1.2

EQUITY BASED COMPENSATION - Schedule of Weighted Average Assumptions Relating to the Valuation of Stock Options (Detail)	9 Months Ended
	Sep. 30, 2021 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average fair value of grants	$ 1.54
Expected volatility	35.00%
Expected term (years)	4 years 6 months
Risk-free interest rate	0.40%
Expected dividend yield	0.00%

INCOME TAXES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Line Items]
Effective income tax rate as a percentage	38.70%		48.00%
Income tax provision or benefit	$ (4,989)	$ 0	$ (2,860)	$ 0	$ 0	$ 0