Cover Page - USD ($)	4 Months Ended
	Dec. 31, 2020	Mar. 25, 2021	Jun. 30, 2020
Document Information [Line Items]
Document Type	10-K/A
Document Annual Report	true
Document Transition Report	false
Amendment Flag	true
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	Golden Falcon Acquisition Corp.
Entity Central Index Key	0001823896
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Shell Company	true
Entity File Number	001-39816
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	850 Library Avenue
Entity Address, Address Line Two	Suite 204
Entity Address, City or Town	Newark
Entity Address, Postal Zip Code	19711
Entity Tax Identification Number	85-2738750
City Area Code	970
Local Phone Number	315-2644
Entity Address, State or Province	DE
Entity Public Float			$ 0
ICFR Auditor Attestation Flag	false
Amendment Description	Golden Falcon Acquisition Corp. (the “Company”, “we”, “our” or “us”) is filing this Amendment No. 1 to its Annual Report on Form 10-K (this “Amendment”) to amend and restate (the “Restatement”) certain items of its Annual Report on Form 10-K for the year ended December 31, 2020, originally filed with the U.S. Securities and Exchange Commission (the “SEC”) on March 31, 2021 (the “Original Filing”). On April 12, 2021, the staff of the Securities and Exchange Commission (the “SEC Staff”) issued a public statement entitled “Staff Statement on Accounting and Reporting Considerations for Warrants issued by Special Purpose Acquisition Companies (“SPACs”)” (the “SEC Staff Statement”). In the SEC Staff Statement, the SEC Staff expressed its view that certain terms and conditions common to SPAC warrants may require the warrants to be classified as liabilities on the SPAC’s balance sheet as opposed to being treated as equity. Since their issuance on December 22, 2020 at the time of our initial public offering, our outstanding warrants to purchase shares of common stock were accounted for as equity within our balance sheet, and after discussion and evaluation, we have concluded that our warrants should be presented as liabilities with subsequent fair value remeasurement. Therefore, we, after consultation with our independent registered public accounting firm, our management and the audit committee of the Company’s board of directors, concluded that our previously issued financial statements for the year ended December 31, 2020 should be restated because of a misapplication in the guidance around accounting for our outstanding warrants, and should no longer be relied upon. Historically, the warrants were reflected as a component of equity as opposed to liabilities on the balance sheet and the statement of operations did not include the subsequent non-cash changes in estimated fair value of the warrants, based on our application of Financial Accounting Standards Board (the “FASB”) Accounting Standards Codification (“ASC”) Topic 815-40, Derivatives and Hedging - Contracts in Entity’s Own Equity (“ASC 815-40”). The views expressed in the SEC Staff Statement were not consistent with our historical interpretation of the specific provisions within our warrant agreements and our application of ASC 815-40 to the warrant agreement. We reassessed our accounting for the warrants issued on December 22, 2020, in light of the SEC Staff Statement. Based on this reassessment, we determined that the warrants should be classified as liabilities measured at fair value upon issuance, with any subsequent changes in fair value reported in our statements of operations each reporting period. The change in accounting for the warrants did not have any impact on our liquidity, cash flows, revenues or costs of operating our business and the other non-cash adjustments to the previously reported financial statements or in any of the periods included in Item 8, Financial Statements and Supplementary Data in this filing. The change in accounting for the warrants does not impact the amounts previously reported for the Company’s cash and cash equivalents, investments held in trust account, operating expenses or total cash flows from operations. This Amendment presents the Original Filing, amended and restated with modifications as necessary to reflect the restatement. The following items in the Original Filing have been amended: • Item 1A, Risk Factors, • Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operation, • Item 8, Financial Statements and Supplementary Data, and • Item 9A, Controls and Procedures. In addition, new certifications by the Company’s principal executive officer and principal financial officer are filed as exhibits (in Exhibits 31.1, 31.2 and 32.1) to this Amendment. Except as described above, this Amendment does not amend, update or change any other items or disclosures contained in the Original Filing, and accordingly, this Amendment does not reflect or purport to reflect any information or events occurring after the original filing date or modify or update those disclosures affected by subsequent events. Accordingly, this Amendment should be read in conjunction with the Original Filing and the Company’s other filings with the SEC.
Units [Member]
Document Information [Line Items]
Trading Symbol	GFX.U
Title of 12(b) Security	Units, each consisting of one share of Class A common stock and one-half of one redeemable warrant
Security Exchange Name	NYSE
Common Class A [Member]
Document Information [Line Items]
Trading Symbol	GFX
Title of 12(b) Security	Class A common stock, $0.0001 par value per share
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		34,500,000
Warrant [Member]
Document Information [Line Items]
Trading Symbol	GFX WS
Title of 12(b) Security	Warrants to purchase one share of Class A common stock
Security Exchange Name	NYSE
Common Class B [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		8,625,000