Accounting Policies - Common Stock Equivalents Excluded From Computation of Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Payment Arrangement, Option
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded (in shares)	18,705	18,795
Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded (in shares)	2,530	570
Warrant
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded (in shares)		220
Convertible Debt Securities
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares excluded (in shares)	9,819	9,653