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Credit Facility and Other Long Term Debt - Components of Convertible Senior Notes (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	May 31, 2020	Dec. 31, 2016	Jun. 30, 2016
Debt Instrument [Line Items]
Total principal payments due	$ 680,919	$ 680,919	$ 1,100,000
Total amount outstanding	672,286	662,531	1,009,951
Credit Facility borrowings	0	0	0
Non-current portion of long-term debt	672,286	662,531	1,009,951
Credit Facility
Debt Instrument [Line Items]
Unamortized debt issuance costs - Credit facility	$ (4,623)	(4,870)	(3,978)
1.50% Convertible Senior Notes
Debt Instrument [Line Items]
Stated interest rate, percentage	1.50%			1.50%
1.50% Convertible Senior Notes \| Convertible Notes
Debt Instrument [Line Items]
Total principal payments due	$ 80,919	80,919	500,000
Unamortized debt discount	0	(9,207)	(73,821)
Unamortized debt issuance costs - Credit facility	$ (677)	(779)	(8,124)
Stated interest rate, percentage	1.50%
3.25% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Total principal payments due	$ 600,000	600,000	600,000
Unamortized debt discount	(1,067)	(1,131)	(1,321)
Unamortized debt issuance costs - Credit facility	$ (2,266)	$ (2,401)	$ (2,805)		$ (5,400)
Stated interest rate, percentage	3.25%					3.25%