Fair Value Measurements - Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Auction Rate Securities Purchase Commitment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Liabilities Beginning Balance		$ 195
Total Realized and Unrealized Gains (Losses)		0
Sales and Settlements		(130)
Purchases and Issuances		0
Transfers In (Out)		0
Liabilities Ending Balance		65
Auction rate securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Assets Beginning Balance	$ 31,804	30,701
Total Realized and Unrealized Losses	0	(131)
Purchases and Issuances	0	1,875
Sales and Settlements	0	(975)
Transfers In (Out)	0	0
Assets Ending Balance	$ 31,804	$ 31,470