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Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Oct. 08, 2021	Dec. 31, 2020	Oct. 07, 2020	Nov. 15, 2019	Jun. 10, 2014
Debt Instrument [Line Items]
Gross long-term debt	$ 1,191,276
Less: Unamortized discount	(91,593)		$ (112,798)
Deferred issuance costs	(9,056)		(11,505)
Total debt	1,090,627		1,579,021
Less: current portion	(54,609)		(396,801)
Total long-term debt, less current portion	1,036,018		1,182,220
Senior Notes \| 4.625% Senior Notes Due in 2030
Debt Instrument [Line Items]
Stated interest rate		4.625%		4.625%
Gross long-term debt	641,276		750,000	$ 750,000
Less: Unamortized discount	(4,259)
Deferred issuance costs	(1,339)
Total debt	635,678
Convertible Debt
Debt Instrument [Line Items]
Gross long-term debt	1,191,276		1,702,414
Convertible Debt \| 3.25% Convertible Notes
Debt Instrument [Line Items]
Stated interest rate						3.25%
Gross long-term debt	0		402,414
Less: Unamortized discount	0		(4,644)			$ (59,000)
Deferred issuance costs	0		(855)
Total debt	0		396,915
Convertible Debt \| 1.75% Convertible Notes
Debt Instrument [Line Items]
Stated interest rate					1.75%
Gross long-term debt	550,000		550,000
Less: Unamortized discount	(87,334)		(102,631)		$ (118,900)
Deferred issuance costs	(7,717)		(8,889)		$ (2,800)
Total debt	454,949		438,480
Loans Payable \| Paycheck Protection Program, CARES Act
Debt Instrument [Line Items]
Gross long-term debt	$ 0		$ 910