Summary of Significant Accounting Policies - Prepaid Expenses and Other Current Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accounts receivable	$ 4,100,000	$ 1,100,000
Accounts receivable, writeoff	0	0	$ 0
Accounts receivable, allowance for doubtful accounts	$ 0	$ 0