Basis of Presentation and Significant Accounting Policies - Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Changes in the Company's contract assets and contract liabilities
Contract asset, Beginning balance	$ 3,000
Contract asset, Additions		$ 0
Contract asset, Ending balance	3,000
Contract liabilities:
Contract liabilities (deferred revenue), Beginning balance	92,068	110,109
Contract liabilities (deferred revenue), Additions	3,803
Contract liabilities (deferred revenue), Deductions	(25,760)	(72)
Contract liabilities (deferred revenue), Ending balance	$ 70,111	$ 110,037