SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
Sep. 30, 2024
Accounting Policies [Abstract]
Reclassifications	Reclassifications Certain prior year amounts have been reclassified to conform to the current year’s presentation.
Revenue Recognition	Revenue Recognition Cryptocurrency Mining Revenue Greenidge has entered into digital asset mining pools by executing contracts with the mining pool operators to perform hash computations for a mining pool. The contracts are terminable at any time at no cost by either party and Greenidge’s enforceable right to compensation begins only when, and lasts as long as, Greenidge performs hash computations for the mining pool operator. In exchange for performing hash computations, Greenidge is entitled to a fractional share of the cryptocurrency award the mining pool operator theoretically receives less the mining pool fees. The agreements entered into with the pool operators pay out based on a Full-Pay-Per-Share (“FPPS”) payout formula, which is a conceptual formula that entitles Greenidge to consideration upon the provision of hash computations to the pool even if a block is not successfully placed by the pool operator. Revenue is measured as the value of the consideration received in the form of cryptocurrency from the pool operator, less the mining pool fees retained by the mining pool operator. Greenidge does not expect any material future changes in mining pool fee rates. In exchange for performing hash computations for the mining pool, the Company is entitled to a fractional share of the cryptocurrency award the mining pool operator theoretically receives (less pool operator fees to the mining pool operator which are netted as a reduction of the transaction price). Greenidge’s fractional share is based on the proportion of hash computations the Company performed for the mining pool operator to the total hash computations contributed by all miners in solving the current algorithm during the 24-hour period. Daily earnings calculated under the FPPS payout formula are calculated from midnight-to-midnight UTC time and are credited to pool members’ accounts at 1:00:00 A.M. UTC. The pool sends Greenidge’s cryptocurrency balance in the account to a digital wallet designated by the Company between 9:00 A.M. and 5:00 P.M. UTC time each day, which Greenidge automatically sells for cash within minutes of receipt, unless Greenidge decides to retain its newly earned bitcoin in connection with its bitcoin retention strategy. The service of performing hash computations for the mining pool operators is an output of Greenidge’s ordinary activities and is the only performance obligation in Greenidge’s contracts with mining pool operators. The cryptocurrency that Greenidge receives as transaction consideration is noncash consideration, which Greenidge measures at fair value on the contract inception date at 0:00:00 UTC on the start date of the contract. The duration of each contract is 24 hours or less and provides the same rate of payment upon renewal. Since the pricing remains the same upon contract renewal, the contract does not provide the applicable mining pool operator with a material right that represents a separate performance obligation. The fair value is based on Greenidge’s primary exchange of the related cryptocurrency which is considered to be Coinbase. The consideration Greenidge earns is variable since it is based on the amount of hash computations provided by both Greenidge and the bitcoin network as a whole. The Company does not constrain this variable consideration because it is probable that a significant reversal in the amount of revenue recognized from the contract will not occur when the uncertainty is subsequently resolved and recognizes the non-cash consideration on the same day that control is transferred, which is the same day as contract inception. Engineering Procurement and Construction Management ("EPCM") Revenue The Company has entered into contracts with customers to perform engineering procurement and construction management services for customers developing cryptocurrency mining facilities. The services defined in the contracts are generally separated into phases, being 1) engineering 2) construction and 3) procurement. While the services discussed above are capable of being distinct and separately identifiable, the Company concluded that the services provided are inputs to produce the combined output to the customer, which is the completed site buildout. Further, the services provided are significantly modified by the other services in the contract. As such, while the performance obligations may be capable of being distinct, they are not distinct in the context of the contract and therefore the promises in the contract are combined into one single performance obligation. The Company recognizes EPCM revenue over time, as performance obligations are satisfied, due to the continuous transfer of control to the customer. The Company utilizes the percentage-of-completion method, based primarily on contract cost incurred to date compared to total estimated contract cost. The percentage-of-completion method, and input method, is used as management considers it to be the best available measure of progress on these contracts. To the extent a contract is canceled, the Company assesses whether there are any remaining goods or services to be provided after cancellation. If there are any remaining goods or services to be provided, the Company follows the guidance under ASC 606 for contract modifications. If there are no remaining goods or services to be provided, the Company considers whether consideration received is refundable or nonrefundable. To the extent consideration received is refundable, the Company recognizes a refund liability, otherwise, it recognizes revenue for the consideration received.
Digital Assets	Digital Assets Digital assets are comprised of bitcoin earned as noncash consideration in exchange for providing hash computations for a mining pool, which are accounted for in connection with the Company’s revenue recognition policy previously disclosed. Digital assets are included in current assets in the consolidated balance sheets due to the Company’s ability to sell it in a highly liquid marketplace and because the Company reasonably expects to liquidate its digital assets to support operations within the next twelve months. The Company adopted ASU 2023-08 during the second quarter of 2024 with an effective date of January 1, 2024. As a result of adopting ASU 2023-08, the Company measures digital assets at fair value as of each reporting period based on UTC closing prices at period-end on the active trading platform that the Company normally transacts and has determined is its principal market for bitcoin. Gains and losses resulting from remeasurements are included within Loss (gain) on digital assets in the consolidated statements of operations and comprehensive loss. Gains and losses resulting from the sale of bitcoin, measured as the difference between the cash proceeds and the carrying basis of bitcoin as determined on a first-in-first-out basis, are also included within Loss (gain) on digital assets in the consolidated statements of operations and comprehensive loss. Digital assets received by the Company as noncash consideration are included as an adjustment to reconcile net loss to cash used in operating activities on the consolidated statements of cash flows. In August 2024, the Company announced its new bitcoin self-mining retention strategy, which enables the Company to accumulate bitcoin from its owned miners. Proceeds from the sale of bitcoin that occur nearly immediately after receipt are included within operating activities on the consolidated statements of cash flows. To the extent the Company holds bitcoin for more than a few days, proceeds from the sale of bitcoin are included within investing activities on the consolidated statements of cash flows. Notwithstanding the foregoing, in connection with this new bitcoin retention strategy, certain amounts of the Company's bitcoin earned from self-mining activities will be held as a treasury reserve asset, as determined in the Company's sole discretion. Prior to the adoption of ASU 2023-08, the Company accounted for digital assets as intangible assets with an indefinite useful life, which are not amortized but assessed for impairment annually, or more frequently, when events or changes in circumstances occur indicating that it is more likely than not that the indefinite-lived asset is impaired. The Company performed an analysis each period to identify whether events or changes in circumstances, principally decreases in the quoted prices on active exchanges, indicated that it was more likely than not that its digital assets were impaired. Digital assets were considered impaired if the carrying value was greater than the lowest intraday quoted price at any time during the period. For quoted prices, the Company used daily exchange data from its principal market. Subsequent reversal of impairment losses were not permitted.
Recent Accounting Pronouncements, Not Yet Adopted and Recent Accounting Pronouncements, Adopted	Recent Accounting Pronouncements, Not Yet Adopted In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. ASU 2023-07 expands public entities’ segment disclosures by requiring disclosure of significant segment expenses that are regularly provided to the chief operating decision maker and included within each reported measure of segment profit or loss, an amount and description of its composition of other segment items, and interim disclosures of a reportable segment’s profit or loss and assets. This guidance becomes effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024 and is required to be applied retrospectively. Early adoption is permitted. The Company is currently evaluating this guidance to determine the impact it may have on its consolidated financial statements disclosures. In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosure. ASU 2023-09 mostly requires, on an annual basis, disclosure of specific categories in an entity’s effective tax rate reconciliation and income taxes paid disaggregated by jurisdiction. The incremental disclosures may be presented on a prospective or retrospective basis. The ASU is effective for fiscal years beginning after December 15, 2024 with early adoption permitted. The Company is currently evaluating the impact the adoption of this ASU will have on its consolidated financial statements and disclosures. In March 2024, the FASB issued ASU 2024-01, Compensation - Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards. ASU 2024-01 clarifies ASC 718 scope application for profits interest and similar awards by adding illustrative examples. This guidance becomes effective for annual periods beginning after December 15, 2024 and interim periods within those annual periods. Early adoption is permitted. The Company is currently evaluating this guidance to determine the impact, but does not expect it to have a material impact on its Condensed Consolidated Financial Statements and related disclosures. In March 2024, the FASB issued ASU 2024-02, Codification Improvements - Amendments to Remove References to the Concept Statements. ASU 2024-02 removes references to various Concept Statements. This ASU is effective for fiscal years beginning after December 15, 2024. Early application of the amendments in the ASU is permitted. ASU 2024-02 can be applied prospectively or retrospectively. The Company is currently evaluating this guidance to determine the impact, but does not expect it to have a material impact on its Condensed Consolidated Financial Statements and related disclosures. Recent Accounting Pronouncements, Adopted In December 2023, the FASB issued ASU No. 2023-08, Intangibles - Goodwill and Other - Crypto Assets (Subtopic 350-60): Accounting for and Disclosure of Crypto Assets ("ASU 2023-08"), which is intended to improve the accounting for and disclosure of crypto assets. The amendments require crypto assets meeting the criteria to be recognized at fair value with changes recognized in net income each reporting period. Upon adoption, a cumulative-effect adjustment is made to the opening balance of retained earnings as of the beginning of the annual reporting period of adoption. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2024, with early adoption permitted. The Company elected to adopt ASU 2023-08 effective January 1, 2024. As a result of adoption, the Company recorded a cumulative-effect adjustment to its Accumulated deficit balance of approximately $0.02 million as of January 1, 2024, as a result of recognizing its bitcoin held as of January 1, 2024, at fair value.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

9 Months Ended

Sep. 30, 2024

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

Cryptocurrency Mining Revenue

Greenidge has entered into digital asset mining pools by executing contracts with the mining pool operators to perform hash computations for a mining pool. The contracts are terminable at any time at no cost by either party and Greenidge’s enforceable right to compensation begins only when, and lasts as long as, Greenidge performs hash computations for the mining pool operator. In exchange for performing hash computations, Greenidge is entitled to a fractional share of the cryptocurrency award the mining pool operator theoretically receives less the mining pool fees. The agreements entered into with the pool operators pay out based on a Full-Pay-Per-Share (“FPPS”) payout formula, which is a conceptual formula that entitles Greenidge to consideration upon the provision of hash computations to the pool even if a block is not successfully placed by the pool operator. Revenue is measured as the value of the consideration received in the form of cryptocurrency from the pool operator, less the mining pool fees retained by the mining pool operator. Greenidge does not expect any material future changes in mining pool fee rates.

In exchange for performing hash computations for the mining pool, the Company is entitled to a fractional share of the cryptocurrency award the mining pool operator theoretically receives (less pool operator fees to the mining pool operator which are netted as a reduction of the transaction price). Greenidge’s fractional share is based on the proportion of hash computations the Company performed for the mining pool operator to the total hash computations contributed by all miners in solving the current algorithm during the 24-hour period. Daily earnings calculated under the FPPS payout formula are calculated from midnight-to-midnight UTC time and are credited to pool members’ accounts at 1:00:00 A.M. UTC. The pool sends Greenidge’s cryptocurrency balance in the account to a digital wallet designated by the Company between 9:00 A.M. and 5:00 P.M. UTC time each day, which Greenidge automatically sells for cash within minutes of receipt, unless Greenidge decides to retain its newly earned bitcoin in connection with its bitcoin retention strategy.

The service of performing hash computations for the mining pool operators is an output of Greenidge’s ordinary activities and is the only performance obligation in Greenidge’s contracts with mining pool operators. The cryptocurrency that Greenidge receives as transaction consideration is noncash consideration, which Greenidge measures at fair value on the contract inception date at 0:00:00 UTC on the start date of the contract. The duration of each contract is 24 hours or less and provides the same rate of payment upon renewal. Since the pricing remains the same upon contract renewal, the contract does not provide the applicable mining pool operator with a material right that represents a separate performance obligation. The fair value is based on Greenidge’s primary exchange of the related cryptocurrency which is considered to be Coinbase. The consideration Greenidge earns is variable since it is based on the amount of hash computations provided by both Greenidge and the bitcoin network as a whole. The Company does not constrain this variable consideration because it is probable that a significant reversal in the amount of revenue recognized from the contract will not occur when the uncertainty is subsequently resolved and recognizes the non-cash consideration on the same day that control is transferred, which is the same day as contract inception.

Engineering Procurement and Construction Management ("EPCM") Revenue

The Company has entered into contracts with customers to perform engineering procurement and construction management services for customers developing cryptocurrency mining facilities. The services defined in the contracts are generally separated into phases, being 1) engineering 2) construction and 3) procurement.

While the services discussed above are capable of being distinct and separately identifiable, the Company concluded that the services provided are inputs to produce the combined output to the customer, which is the completed site buildout. Further, the services provided are significantly modified by the other services in the contract. As such, while the performance obligations may be capable of being distinct, they are not distinct in the context of the contract and therefore the promises in the contract are combined into one single performance obligation.

The Company recognizes EPCM revenue over time, as performance obligations are satisfied, due to the continuous transfer of control to the customer. The Company utilizes the percentage-of-completion method, based primarily on contract cost incurred to date compared to total estimated contract cost. The percentage-of-completion method, and input method, is used as management considers it to be the best available measure of progress on these contracts.

To the extent a contract is canceled, the Company assesses whether there are any remaining goods or services to be provided after cancellation. If there are any remaining goods or services to be provided, the Company follows the guidance under ASC 606 for contract modifications. If there are no remaining goods or services to be provided, the Company considers whether consideration received is refundable or nonrefundable. To the extent consideration received is refundable, the Company recognizes a refund liability, otherwise, it recognizes revenue for the consideration received.

Digital Assets

Digital assets are comprised of bitcoin earned as noncash consideration in exchange for providing hash computations for a mining pool, which are accounted for in connection with the Company’s revenue recognition policy previously disclosed. Digital assets are included in current assets in the consolidated balance sheets due to the Company’s ability to sell it in a highly liquid marketplace and because the Company reasonably expects to liquidate its digital assets to support operations within the next twelve months.

The Company adopted ASU 2023-08 during the second quarter of 2024 with an effective date of January 1, 2024. As a result of adopting ASU 2023-08, the Company measures digital assets at fair value as of each reporting period based on UTC closing prices at period-end on the active trading platform that the Company normally transacts and has determined is its principal market for bitcoin.

Gains and losses resulting from remeasurements are included within Loss (gain) on digital assets in the consolidated statements of operations and comprehensive loss. Gains and losses resulting from the sale of bitcoin, measured as the difference between the cash proceeds and the carrying basis of bitcoin as determined on a first-in-first-out basis, are also included within Loss (gain) on digital assets in the consolidated statements of operations and comprehensive loss.

Digital assets received by the Company as noncash consideration are included as an adjustment to reconcile net loss to cash used in operating activities on the consolidated statements of cash flows. In August 2024, the Company announced its new bitcoin self-mining retention strategy, which enables the Company to accumulate bitcoin from its owned miners. Proceeds from the sale of bitcoin that occur nearly immediately after receipt are included within operating activities on the consolidated statements of cash flows. To the extent the Company holds bitcoin for more than a few days, proceeds from the sale of bitcoin are included within investing activities on the consolidated statements of cash flows. Notwithstanding the foregoing, in connection with this new bitcoin retention strategy, certain amounts of the Company's bitcoin earned from self-mining activities will be held as a treasury reserve asset, as determined in the Company's sole discretion.

Prior to the adoption of ASU 2023-08, the Company accounted for digital assets as intangible assets with an indefinite useful life, which are not amortized but assessed for impairment annually, or more frequently, when events or changes in circumstances occur indicating that it is more likely than not that the indefinite-lived asset is impaired. The Company performed an analysis each period to identify whether events or changes in circumstances, principally decreases in the quoted prices on active exchanges, indicated that it was more likely than not that its digital assets were impaired. Digital assets were considered impaired if the carrying value was greater than the lowest intraday quoted price at any time during the period. For quoted prices, the Company used daily exchange data from its principal market. Subsequent reversal of impairment losses were not permitted.

Recent Accounting Pronouncements, Not Yet Adopted and Recent Accounting Pronouncements, Adopted

Recent Accounting Pronouncements, Not Yet Adopted

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. ASU 2023-07 expands public entities’ segment disclosures by requiring disclosure of significant segment expenses that are regularly provided to the chief operating decision maker and included within each reported measure of segment profit or loss, an amount and description of its composition of other segment items, and interim disclosures of a reportable segment’s profit or loss and assets. This guidance becomes effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024 and is required to be applied retrospectively. Early adoption is permitted. The Company is currently evaluating this guidance to determine the impact it may have on its consolidated financial statements disclosures.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosure. ASU 2023-09 mostly requires, on an annual basis, disclosure of specific categories in an entity’s effective tax rate reconciliation and income taxes paid disaggregated by jurisdiction. The incremental disclosures may be presented on a prospective or retrospective basis. The ASU is effective for fiscal years beginning after December 15, 2024 with early adoption permitted. The Company is currently evaluating the impact the adoption of this ASU will have on its consolidated financial statements and disclosures.

In March 2024, the FASB issued ASU 2024-01, Compensation - Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards. ASU 2024-01 clarifies ASC 718 scope application for profits interest and similar awards by adding illustrative examples. This guidance becomes effective for annual periods beginning after December 15, 2024 and interim periods within those annual periods. Early adoption is permitted. The Company is currently evaluating this guidance to determine the impact, but does not expect it to have a material impact on its Condensed Consolidated Financial Statements and related disclosures.

In March 2024, the FASB issued ASU 2024-02, Codification Improvements - Amendments to Remove References to the Concept Statements. ASU 2024-02 removes references to various Concept Statements. This ASU is effective for fiscal years beginning after December 15, 2024. Early application of the amendments in the ASU is permitted. ASU 2024-02 can be applied prospectively or retrospectively. The Company is currently evaluating this guidance to determine the impact, but does not expect it to have a material impact on its Condensed Consolidated Financial Statements and related disclosures.

Recent Accounting Pronouncements, Adopted

In December 2023, the FASB issued ASU No. 2023-08, Intangibles - Goodwill and Other - Crypto Assets (Subtopic 350-60): Accounting for and Disclosure of Crypto Assets ("ASU 2023-08"), which is intended to improve the accounting for and disclosure of crypto assets. The amendments require crypto assets meeting the criteria to be recognized at fair value with changes recognized in net income each reporting period. Upon adoption, a cumulative-effect adjustment is made to the opening balance of retained earnings as of the beginning of the annual reporting period of adoption. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2024, with early adoption permitted. The Company elected to adopt ASU 2023-08 effective January 1, 2024. As a result of adoption, the Company recorded a cumulative-effect adjustment to its Accumulated deficit balance of approximately $0.02 million as of January 1, 2024, as a result of recognizing its bitcoin held as of January 1, 2024, at fair value.