Significant Accounting Policies - Concentration of Credit Risk (Details) - Customer concentration risk - customer	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Concentration of Credit Risk
Customers (in customers)	0	0	0
Concentration risk (in percent)	10.00%	10.00%	10.00%
Accounts receivable
Concentration of Credit Risk
Customers (in customers)	0	0
Concentration risk (in percent)	10.00%	10.00%