Fair Value of Financial Instruments - Schedule of Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Level 1
Liabilities
Obligation to issue registered shares of Class A Common Stock	$ 0
Level 1 | Fair Value, Recurring
Liabilities
Conditional obligation		$ 0
Level 1 | Fair Value, Recurring | Private Warrants
Liabilities
Warrant liability	0
Level 1 | Fair Value, Recurring | Notes payable
Liabilities
Notes payable	0	0
Level 1 | Fair Value, Recurring | Affiliated Entity
Liabilities
Notes payable		0
Level 1 | Fair Value, Recurring | Money market funds
Assets
Money market funds	570,000
Level 2
Liabilities
Obligation to issue registered shares of Class A Common Stock	0
Level 2 | Fair Value, Recurring
Liabilities
Conditional obligation		0
Level 2 | Fair Value, Recurring | Private Warrants
Liabilities
Warrant liability	0
Level 2 | Fair Value, Recurring | Notes payable
Liabilities
Notes payable	0	0
Level 2 | Fair Value, Recurring | Affiliated Entity
Liabilities
Notes payable		0
Level 2 | Fair Value, Recurring | Money market funds
Assets
Money market funds	0
Level 3
Liabilities
Obligation to issue registered shares of Class A Common Stock	22,511
Level 3 | Fair Value, Recurring
Liabilities
Conditional obligation		1,128
Level 3 | Fair Value, Recurring | Private Warrants
Liabilities
Warrant liability	1,153
Level 3 | Fair Value, Recurring | Notes payable
Liabilities
Notes payable	188,589	59,742
Level 3 | Fair Value, Recurring | Affiliated Entity
Liabilities
Notes payable		$ 32,949
Level 3 | Fair Value, Recurring | Money market funds
Assets
Money market funds	$ 0