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Summary of Significant Accounting Policies (Policies) | 3 Months Ended | 12 Months Ended
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Mar. 31, 2021 | Dec. 31, 2020
Basis of Presentation | Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) and include the accounts of the Company, its wholly-owned subsidiaries, and consolidated variable interest entities (“VIEs”). All intercompany balances and transactions have been eliminated in consolidation. | Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) and include the accounts of the Company, its wholly-owned subsidiaries, and consolidated variable interest entities (“VIEs”). All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates | Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Actual results could differ from those estimates and such differences could be material to the financial position and results of operations. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, depreciable life of energy systems; the amortization of financing obligations; deferred commissions and contract fulfillment costs; the valuation of energy storage systems, internally developed software, and asset retirement obligations; and the fair value of equity instruments, equity-based instruments, warrant liabilities and embedded derivatives. | Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Actual results could differ from those estimates and such differences could be material to the financial position and results of operations. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, depreciable life of energy storage systems; the amortization of financing obligations; deferred commissions and contract fulfillment costs; the valuation of energy storage systems, internally developed software, and asset retirement obligations; and the fair value of equity instruments, equity- based instruments, warrant liabilities, and embedded derivatives.
Cash and Cash Equivalents |  | Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity date of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents are maintained at financial institutions. The Company maintains all cash in a highly liquid form to meet current obligations.
Fair Value of Financial Instruments | Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels which are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1 — Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2 — Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3 — Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. Financial assets and liabilities held by the Company measured at fair value on a recurring basis as of March 31, 2021 and December 31, 2020 include cash and cash equivalents and warrant liabilities. | Fair Value of Financial Instruments Assets and liabilities recorded at fair value in the consolidated financial statements are categorized based upon the level of judgment associated with the inputs used to measure their fair value. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). Hierarchical levels which are directly related to the amount of subjectivity associated with the inputs to the valuation of these assets or liabilities are as follows: Level 1 — Unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. Level 2 — Inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. Level 3 — Unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to their fair value measurement. The Company’s assessment of the significance of a specific input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability. Financial assets and liabilities held by the Company measured at fair value on a recurring basis as of December 31, 2020 and 2019 include cash and cash equivalents, warrant liabilities, and embedded derivatives which are bifurcated from the host financial instrument.
Net Loss Per Share Attributable to Common Stockholders |  | Net Loss Per Share Attributable to Common Stockholders Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. Under the two-class method, net loss is attributed to common stockholders and participating securities based on their participation rights. The Company considers all series of its convertible preferred stock to be participating securities. Under the two- class method, the net loss attributable to common stockholders is not allocated to the convertible preferred stock as the holders of the Company’s convertible preferred stock do not have a contractual obligation to share in the Company’s losses. Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period, without consideration for potential dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted- average number of common shares and common share equivalents of potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, convertible preferred stock, convertible notes, warrants and common stock options are considered to be potentially dilutive securities. As the Company was in a net loss position for the years ended December 31, 2020 and 2019, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders because the effects of potentially dilutive securities are antidilutive.
Income Taxes |  | Income Taxes The Company uses the asset and liability method of accounting for income taxes based on Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 740, Accounting for Income Taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between financial statement carrying amounts and the tax basis of existing assets and liabilities. The Company records a valuation allowance to reduce tax assets to an amount for which realization is more likely than not. There are certain charges that are not deductible for tax purposes. In evaluating the ability to recover its deferred income tax assets, the Company considers all available positive and negative evidence, including its operating results, ongoing tax planning, and forecasts of future taxable income on a jurisdiction-by-jurisdiction basis. In the event the Company determines that it would be able to realize its deferred income tax assets in the future in excess of their net recorded amount, it would make an adjustment to the valuation allowance that would reduce the provision for income taxes. Conversely, in the event that all or part of the net deferred tax assets are determined not to be realizable in the future, an adjustment to the valuation allowance would be charged to earnings in the period such determination is made. The Company recognizes the tax benefit from uncertain tax positions in accordance with GAAP, which prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of uncertain tax positions taken or expected to be taken in the Company’s tax return. No liability related to uncertain tax positions has been recognized in the financial statements. The Company includes interest and penalties for uncertain tax positions in the financial statements as a component of income tax expense. No accrual has been deemed necessary as of December 31, 2020 and 2019.
Recently Adopted Accounting Standards and Recently Issued Accounting Standards | Recently Adopted Accounting Standards In August 2018, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement. The amendments applicable to the Company on, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements and the narrative description of measurement uncertainty should be prospectively applied in the initial fiscal year of adoption. All other amendments applicable to the Company should be applied retrospectively to all periods presented upon their effective date. The Company adopted ASU 2018-13 as of January 1, 2020. The Company’s disclosures related to its level 3 financial instruments were not materially impacted for the periods presented. See Note 4, Fair Value Measurements, for more information. In August 2018, the FASB issued ASU 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). The intent of this pronouncement is to align the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal- use software as defined in ASC 350-40. Under ASU 2018-15, the capitalized implementation costs related to a cloud computing arrangement will be amortized over the term of the arrangement and all capitalized implementation amounts will be required to be presented in the same line items of the financial statements as the related hosting fees. ASU 2018-15 is effective for public and private companies’ fiscal years beginning after December 15, 2019, and December 15, 2020, respectively, and interim periods within those fiscal years, with early adoption permitted. The Company adopted ASU 2018-15 as of January 1, 2021. The adoption did not have a material impact to the Company’s condensed consolidated financial statements. Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, and subsequent related ASUs, which amends the guidance on the impairment of financial instruments by requiring measurement and recognition of expected credit losses for financial assets held. This ASU is effective for public and private companies’ fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2019, and December 15, 2022, respectively. The Company expects to adopt ASU 2016-13 under the private company transition guidance beginning January 1, 2023 and is currently assessing the impact, if any, the guidance will have on the Company’s consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”). ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. ASU 2019-12 will be effective for public entities for interim and annual periods beginning after December 15, 2020, with early adoption permitted. ASU 2019-12 will be effective for private entities for annual periods beginning after December 15, 2021, and interim periods beginning after December 15, 2020, with early adoption permitted. The Company plans to adopt ASU 2019-12 for the fiscal year beginning January 1, 2022 and is currently assessing the impact, if any, the guidance will have on the Company’s consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt — Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (Subtopic 815-40) — Accounting For Convertible Instruments and Contracts in an Entity’s Own Equity. The ASU simplifies accounting for convertible instruments by removing major separation models required under current GAAP. Consequently, more convertible debt instruments will be reported as a single liability instrument with no separate accounting for embedded conversion features. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception, which will permit more equity contracts to qualify for it. The ASU also simplifies the diluted net income per share calculation in certain areas. The new guidance is effective for annual and interim periods beginning after December 15, 2023, and early adoption is permitted for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company plans to adopt 2020-06 for the fiscal year beginning January 1, 2024 and is currently evaluating the impact that this new guidance will have on the Company’s financial statements. | Recently Adopted Accounting Standards In August 2018, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement. The amendments applicable to the Company on the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements and the narrative description of measurement uncertainty should be prospectively applied in the initial fiscal year of adoption. All other amendments applicable to the Company should be applied retrospectively to all periods presented upon their effective date. The Company adopted ASU 2018-13 as of January 1, 2020. The Company’s disclosures related to its level 3 financial instruments were not materially impacted for the periods presented. See Note 4, Fair Value Measurements, for more information. Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, and subsequent related ASUs, which amends the guidance on the impairment of financial instruments by requiring measurement and recognition of expected credit losses for financial assets held. This ASU is effective for public and private companies’ fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2019, and December 15, 2022, respectively. The Company expects to adopt ASU 2016-13 under the private company transition guidance beginning January 1, 2023 and is currently assessing the impact, if any, the guidance will have on the Company’s consolidated financial statements. In August 2018, the FASB issued ASU 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). The intent of this pronouncement is to align the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal- use software as defined in ASC 350-40. Under ASU 2018-15, the capitalized implementation costs related to a cloud computing arrangement will be amortized over the term of the arrangement and all capitalized implementation amounts will be required to be presented in the same line items of the financial statements as the related hosting fees. ASU 2018-15 is effective for public and private companies’ fiscal years beginning after December 15, 2019, and December 15, 2020, respectively, and interim periods within those fiscal years, with early adoption permitted. The Company will adopt ASU 2018-15 for the fiscal year beginning January 1, 2021, and does not expect the adoption to have a material impact on the Company’s consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”). ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. ASU 2019-12 will be effective for public entities for interim and annual periods beginning after December 15, 2020, with early adoption permitted. ASU 2019-12 will be effective for private entities for annual periods beginning after December 15, 2021, and interim periods beginning after December 15, 2020, with early adoption permitted. The Company plans to adopt ASU 2019-12 for the fiscal year beginning January 1, 2022 and is currently assessing the impact, if any, the guidance will have on the Company’s consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt — Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (Subtopic 815-40) — Accounting For Convertible Instruments and Contracts in an Entity’s Own Equity. The ASU simplifies accounting for convertible instruments by removing major separation models required under current GAAP. Consequently, more convertible debt instruments will be reported as a single liability instrument with no separate accounting for embedded conversion features. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception, which will permit more equity contracts to qualify for it. The ASU also simplifies the diluted net income per share calculation in certain areas. The new guidance is effective for annual and interim periods beginning after December 15, 2023, and early adoption is permitted for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company plans to adopt 2020-06 for the fiscal year beginning January 1, 2024 and is currently evaluating the impact that this new guidance will have on the Company’s financial statements.
Star Peak Energy Transition Corp [Member] |  |
Basis of Presentation | Basis of Presentation ​ The accompanying unaudited consolidated condensed financial statements of the Company, including the accounts of the Company’s wholly-owned subsidiary, STPK Merger Sub Corp, have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) for interim financial information and Article 8 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP. all adjustments (consisting of normal accruals) considered for a fair presentation have been included. All intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, operating results for the periods presented are not necessarily indicative of the results that may be expected for the year ending December 31, 2021, or any other future period. ​ The accompanying unaudited consolidated condensed financial statements should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10K/A filed with the SEC on April 26, 2021. | Basis of Presentation The accompanying consolidated financial statements are presented in U.S. dollars, in conformity with accounting principles generally accepted in the United States of America (“GAAP”) for financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”), and include the accounts of the Company’s wholly-owned subsidiary, STPK Merger Sub Corp. All intercompany balances and transactions have been eliminated in consolidation. As described in Note 2-Restatement of Previously Issued Financial Statements, the Company's financial statements for the year ended December 31, 2020, and for the quarter ended September 30, 2020 (collectively, the "Affected Periods"), are restated in this Annual Report on Form 10-K/A (Amendment No. 1) (this "Annual Report") to correct the misapplication of accounting guidance related to the Company's warrants in the Company's previously issued audited and unaudited condensed financial statements for such periods. The restated financial statements are indicated as "Restated" in the audited and unaudited condensed financial statements and accompanying notes, as applicable. See Note 2-Restatement of Previously Issued Financial Statements for further discussion.
Emerging Growth Company | Emerging Growth Company ​ The Company is an “emerging growth company,” as defined in Section 2(a) of the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and it may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, reduced disclosure obligations regarding executive compensation in its periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. Further, Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that an emerging growth company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such an election to opt out is irrevocable. The Company has elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, the Company, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of the Company’s unaudited consolidated condensed financial statements with another public company that is neither an emerging growth company nor an emerging growth company that has opted out of using the extended transition period difficult or impossible because of the potential differences in accounting standards used. | Emerging Growth Company The Company is an “emerging growth company,” as defined in Section 2(a) of the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and it may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, reduced disclosure obligations regarding executive compensation in its periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. Further, Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that an emerging growth company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such an election to opt out is irrevocable. The Company has elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, the Company, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of the Company’s consolidated financial statements with another public company that is neither an emerging growth company nor an emerging growth company that has opted out of using the extended transition period difficult or impossible because of the potential differences in accounting standards used.
Use of Estimates | Use of Estimates ​ The preparation of unaudited consolidated condensed financial statements in conformity with U.S. GAAP requires the Company’s management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the unaudited consolidated condensed financial statements and the reported amounts of revenues and expenses during the reporting period. Making estimates requires management to exercise significant judgment. It is at least reasonably possible that the estimate of the effect of a condition, situation or set of circumstances that existed at the date of the unaudited consolidated condensed financial statements, which management considered in formulating its estimate, could change in the near term due to one or more future confirming events. Accordingly, the actual results could differ significantly from those estimates. | Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Making estimates requires management to exercise significant judgment. It is at least reasonably possible that the estimate of the effect of a condition, situation or set of circumstances that existed at the date of the consolidated financial statements, which management considered in formulating its estimate, could change in the near term due to one or more future confirming events. Actual results could differ from those estimates.
Cash and Cash Equivalents | Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. There were no cash equivalents at March 31, 2021 and December 31, 2020. | Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. There were no cash equivalents at December 31, 2020 and 2019.
Concentration of Credit Risk | Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash accounts in a financial institution, which, at times, may exceed the Federal Depository Insurance Coverage of $250,000, and investments held in Trust Account. The Company has not experienced losses on these accounts and management believes the Company is not exposed to significant risks on such accounts. | Concentration of Credit Risk Financial instruments that potentially subject the Company to concentration of credit risk consist of cash accounts in a financial institution which, at times, may exceed the Federal depository insurance coverage of $250,000, and investments held in Trust Account. The Company has not experienced losses on these accounts and management believes the Company is not exposed to significant risks on such accounts.
Investments Held in the Trust Account | Investments Held in Trust Account The Company’s portfolio of investments is comprised solely of U.S. government securities, within the meaning set forth in Section 2(a)(16) of the Investment Company Act, with a maturity of 185 days or less, or investments in money market funds that invest in U.S. government securities, or a combination thereof. The Company’s investments held in the Trust Account are classified as trading securities. Trading securities are presented on the consolidated condensed balance sheets at fair value at the end of each reporting period. Gains and losses resulting from the change in fair value of these securities is included in gain on investment (net), dividends and interest held in Trust Account in the accompanying unaudited consolidated condensed statements of operations. The estimated fair values of investments held in the Trust Account are determined using available market information. | Investments Held in the Trust Account The Company’s portfolio of investments held in the Trust Account is comprised of U.S. government securities, within the meaning set forth in Section 2(a)(16) of the Investment Company Act, with a maturity of 185 days or less, or investments in money market funds that invest in U.S. government securities, or a combination thereof. The Company’s investments held in the Trust Account are classified as trading securities. Trading securities are presented on the consolidated balance sheets at fair value at the end of each reporting period. Gains and losses resulting from the change in fair value of these securities is included in net gain from investments held in the Trust Account in the accompanying consolidated statements of operations. The estimated fair values of investments held in the Trust Account are determined using available market information.
Fair Value of Financial Instruments | Fair Value of Financial Instruments Fair value is defined as the price that would be received for sale of an asset or paid for transfer of a liability, in an orderly transaction between market participants at the measurement date. U.S. GAAP establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). These tiers include:
| ● | Level 1, defined as observable inputs such as quoted prices for identical instruments in active markets;
| ● | Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable such as quoted prices for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active; and
| ● | Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions, such as valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.
In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. As of March 31, 2021 and December 31, 2020, the carrying values of cash, accounts payable, accrued expenses, and franchise tax payable approximate their fair values due to the short-term nature of the instruments. The Company’s portfolio of investments held in the Trust Account is comprised of investments in U.S. Treasury securities with an original maturity of 185 days or less or investments in money market funds that invest in U.S. government securities, or a combination thereof. The fair value for trading securities is determined using quoted market prices in active markets. | Fair Value of Financial Instruments Fair value is defined as the price that would be received for sale of an asset or paid for transfer of a liability, in an orderly transaction between market participants at the measurement date. GAAP establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). These tiers include:
| ● | Level 1, defined as observable inputs such as quoted prices (unadjusted) for identical instruments in active markets;
| ● | Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable such as quoted prices for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active; and
| ● | Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions, such as valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.
In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. As of December 31, 2020 and 2019, the carrying values of cash, prepaid expenses, accounts payable, accrued expenses and franchise tax payable approximate their fair values due to the short-term nature of the instruments. The Company’s investments held in Trust Account are comprised of investments in U.S. Treasury securities with an original maturity of 185 days or less or investments in a money market funds that comprise only U.S. treasury securities and are recognized at fair value. The fair value of investments held in Trust Account is determined using quoted prices in active markets.
Offering Costs Associated with the Initial Public Offering | Offering Costs Associated with the Initial Public Offering Offering costs consisted of legal, accounting, underwriting fees and other costs incurred through the Initial Public Offering that were directly related to the Initial Public Offering. Offering costs are allocated to the separable financial instruments issued in the Initial Public Offering based on a relative fair value basis, compared to total proceeds received. Offering costs associated with warrant liabilities are expensed as incurred, presented as non-operating expenses in the statements of operations. Offering costs associated with the Class A common stock were charged to stockholders' equity upon the completion of the Initial Public Offering. | Offering Costs Associated with the Initial Public Offering The Company complies with the requirements of the ASC 340-10-S99-1 and SEC Staff Accounting Bulletin Topic 5A– “Expenses of Offering.” Offering costs consist of costs incurred in connection with the formation and preparation for the Initial Public Offering. These costs, together with the underwriting discount, were charged to additional paid- in capital upon the completion of the Initial Public Offering.
Class A Common Stock Subject to Possible Redemption | Class A Common Stock Subject to Possible Redemption The Company accounts for its Class A common stock subject to possible redemption in accordance with the guidance in ASC Topic 480 “Distinguishing Liabilities from Equity.” Class A common stock subject to mandatory redemption (if any) is classified as a liability instrument and measured at fair value. Shares of conditionally redeemable Class A common stock (including Class A common stock that features redemption rights that are either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) are classified as temporary equity. At all other times, Class A common stock are classified as stockholders’ equity. The Company’s Class A common stock features certain redemption rights that are considered to be outside of the Company’s control and subject to the occurrence of uncertain future events. Accordingly, at March 31, 2021 and December 31, 2020, 8,640,832 and 24,275,528 shares of Class A common stock subject to possible redemption are presented as temporary equity, respectively, outside of the stockholders’ equity section of the Company’s consolidated condensed balance sheets. | Class A Common Stock Subject to Possible Redemption The Company accounts for its Class A common stock subject to possible redemption in accordance with the guidance in ASC Topic 480 “Distinguishing Liabilities from Equity.” Shares of Class A common stock subject to mandatory redemption (if any) are classified as liability instruments and are measured at fair value. Shares of conditionally redeemable Class A common stock (including Class A common stock that feature redemption rights that are either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) are classified as temporary equity. At all other times, shares of Class A common stock are classified as stockholders’ equity. The Company’s Class A common stock features certain redemption rights that are considered to be outside of the Company’s control and subject to the occurrence of uncertain future events. Accordingly, at December 31, 2020, 24,275,528 shares of Class A common stock subject to possible redemption are presented as temporary equity, outside of the stockholders’ equity section of the Company’s consolidated balance sheet.
Net Loss Per Share Attributable to Common Stockholders | Net Income (Loss) Per Share of Common Stock Net income (loss) per share of common stock is computed by dividing net income (loss) by the weighted-average number of common stock outstanding during the periods. The Company has not considered the effect of the warrants sold in the Initial Public Offering and the Private Placement to purchase up to an aggregate of 19,967,302 shares of the Company’s Class A common stock in the calculation of the diluted income per share, since their inclusion would be anti-dilutive under the treasury stock method. As a result, diluted earnings per share of common stock is the same as basic earnings per share of common stock for the periods presented. The Company’s unaudited consolidated condensed statements of operations include a presentation of income (loss) per share for common stock subject to redemption in a manner similar to the two-class method of income (loss) per share. Net income per share, basic and diluted for Class A common stock is calculated by dividing the gain on investment (net), dividends and interest held in Trust Account of approximately $35,000, net of applicable taxes available to be withdrawn from the Trust Account of approximately $35,000, by the weighted average number of Class A common stock outstanding for the three months ended March 31, 2021. Net loss per share, basic and diluted for Class B common stock is calculated by dividing the net loss of approximately $156.3 million and $0 for the three months ended March 31, 2021 and 2020, respectively, less income attributable to Class A common stock of $0 for each period, by the weighted average number of Class B common stock outstanding for the periods. | Net Loss Per Common Share Net loss per share of common stock is computed by dividing net loss applicable to stockholders by the weighted average number of shares of common stock outstanding during the periods. The Company has not considered the effect of the warrants sold in the Initial Public Offering and Private Placement to purchase an aggregate of 19,967,302 shares of Class A common stock in the calculation of diluted earnings per share, since their inclusion would be anti- dilutive under the treasury stock method. As a result, diluted earnings per share is the same as basic earnings per share for the periods presented. The Company’s consolidated statement of operations includes a presentation of income per share for common stock subject to redemption in a manner similar to the two-class method of income per share. Net income per share, basic and diluted for Class A common stock is calculated by dividing the investment income earned on the Trust Account of approximately $137,000, net of applicable franchise taxes of approximately $137,000 for the year ended December 31, 2020, by the weighted average number of shares of Class A common stock outstanding for the periods. Net loss per share, basic and diluted for Class B common stock for the year ended December 31, 2020 is calculated by dividing the general and administration expenses of approximately $3.3 million, change in fair value of derivative warrant liabilities of $109.3 million and franchise taxes of $63,000, resulting in a net loss of approximately $112.6 million, by the weighted average number of Class B common stock outstanding for the period.
Income Taxes | Income Taxes The Company complies with the accounting and reporting requirements of Financial Accounting Standards Board Accounting Standard Codification, or FASB ASC, 740, “Income Taxes,” which requires an asset and liability approach to financial accounting and reporting for income taxes. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. FASB ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more-likely-than-not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense. | Income Taxes The Company complies with the accounting and reporting requirements of Financial Accounting Standards Board Accounting Standard Codification, or FASB ASC, 740, “Income Taxes,” which requires an asset and liability approach to financial accounting and reporting for income taxes. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. FASB ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more-likely-than-not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense.
Derivative warrant liabilities | Derivative warrant liabilities ​ The Company does not use derivative instruments to hedge exposures to cash flow, market, or foreign currency risks. The Company evaluates all of its financial instruments, including issued stock purchase warrants, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives, pursuant to ASC 480 and ASC 815-15. The classification of derivative instruments, including whether such instruments should be recorded as liabilities or as equity, is re-assessed at the end of each reporting period. The Company accounts for its 19,967,302 common stock warrants issued in connection with its Initial Public Offering (12,786,168) and Private Placement (7,181,134) as derivative warrant liabilities in accordance with ASC 815-40. Accordingly, the Company recognizes the warrant instruments as liabilities at fair value and adjusts the instruments to fair value at each reporting period. The liabilities are subject to re-measurement at each balance sheet date until exercised, and any change in fair value is recognized in the Company’s statements of operations. The fair value of the Private Placement Warrants have been estimated using a Monte Carlo simulation model each measurement date. The fair value of the warrants issued in connection with the Public Offering were initially measured at fair value using a Monte Carlo simulation model and subsequently measured based on the listed market price of such warrants. | Derivative warrant liabilities The Company does not use derivative instruments to hedge exposures to cash flow, market, or foreign currency risks. The Company evaluates all of its financial instruments, including issued stock purchase warrants, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives, pursuant to ASC 480 and ASC 815-15. The classification of derivative instruments, including whether such instruments should be recorded as liabilities or as equity, is re-assessed at the end of each reporting period. The Company accounts for its 19,967,302 common stock warrants issued in connection with its Initial Public Offering (12,786,168) and Private Placement (7,181,134) as derivative warrant liabilities in accordance with ASC 815-40. Accordingly, the Company recognizes the warrant instruments as liabilities at fair value and adjusts the instruments to fair value at each reporting period. The liabilities are subject to re-measurement at each balance sheet date until exercised, and any change in fair value is recognized in the Company’s statement of operations. The fair value of warrants issued by the Company in connection with the Public Offering and Private Placement has been estimated using Monte-Carlo simulations at each measurement date.
Recently Adopted Accounting Standards and Recently Issued Accounting Standards | Recent Adopted Accounting Standards In August 2020, the FASB issued Accounting Standards Update (“ASU”) No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies accounting for convertible instruments by removing major separation models required under current GAAP. The ASU also removes certain settlement conditions that are required for equity-linked contracts to qualify for the derivative scope exception, and it simplifies the diluted earnings per share calculation in certain areas. The Company adopted ASU 2020-06 on January 1, 2021. Adoption of the ASU did not impact the Company’s financial position, results of operations or cash flows. Recent Issued Accounting Standards ​ The Company’s management does not believe that any recently issued, but not yet effective, accounting standards updates, if currently adopted, would have a material effect on the accompanying financial statement. | Recent Accounting Pronouncements Management does not believe that any recently issued, but not yet effective, accounting pronouncements, if currently adopted, would have an effect on the Company’s consolidated financial statements.

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