Long-Term Debt - Narrative (Details)					3 Months Ended		12 Months Ended
	Oct. 07, 2020 USD ($) fiscalQuarterPeriod	Nov. 15, 2019 USD ($) tradingDay	Jun. 27, 2017 USD ($)	Jun. 10, 2014 USD ($) tradingDay	Dec. 31, 2020 USD ($) tradingDay $ / shares	Dec. 31, 2019 USD ($) tradingDay	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Redemption premium							$ 29,250,000	$ 0	$ 0
Gain (loss) on extinguishment of debt							(37,969,000)	0	0
Unamortized debt discount					$ 112,798,000	$ 139,981,000	112,798,000	139,981,000
Total fair value adjustments reported in earnings							0	(800,000)	0
Debt issuance costs					11,505,000	14,058,000	11,505,000	14,058,000
Proceeds from line of credit							0	185,000,000	0
Lines of credit paid off							0	185,000,000	0
Interest expense							133,800,000	70,200,000	63,500,000
Outstanding debt originating from the Paycheck Protection Program					1,703,324,000		1,703,324,000
Senior Notes | 6.0% Senior Notes
Debt Instrument [Line Items]
Face amount			$ 650,000,000
Stated interest rate	6.00%
Proceeds from debt, net of issuance costs			$ 636,500,000
Redemption payment of senior notes	$ 694,600,000
Redemption premium	29,200,000
Payments of interest	15,400,000
Gain (loss) on extinguishment of debt	(38,000,000.0)
Fair value of senior notes						689,800,000		689,800,000
Unamortized debt discount						8,425,000		8,425,000
Debt issuance costs						1,466,000		1,466,000
Outstanding debt originating from the Paycheck Protection Program					0	650,000,000	0	650,000,000
Senior Notes | 4.625% Senior Notes
Debt Instrument [Line Items]
Face amount	$ 750,000,000
Stated interest rate	4.625%
Proceeds from debt, net of issuance costs	$ 742,700,000
Covenant, leverage ratio, minimum	3.5
Fair value of senior notes					796,900,000		796,900,000
Percentage principal outstanding to be eligible for redemption	50.00%
Covenant, EBITDA minimum	50.00%
Covenant, EBITDA minimum, fiscal quarter period | fiscalQuarterPeriod	4
Covenant restricted payment threshold	$ 250,000,000
Unamortized debt discount					5,523,000		5,523,000
Debt issuance costs					1,761,000		1,761,000
Outstanding debt originating from the Paycheck Protection Program					750,000,000	0	750,000,000	0
Senior Notes | 4.625% Senior Notes | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Percentage of principal amount redeemed	40.00%
Redemption price, percentage	104.625%
Senior Notes | 4.625% Senior Notes | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price, percentage	100.00%
Convertible Debt
Debt Instrument [Line Items]
Outstanding debt originating from the Paycheck Protection Program					1,702,414,000	1,602,500,000	1,702,414,000	1,602,500,000
Convertible Debt | 3.25% Convertible Notes
Debt Instrument [Line Items]
Face amount				$ 402,500,000
Stated interest rate				3.25%
Percentage of principal amount redeemed				100.00%
Fair value of senior notes					$ 593,100,000	$ 583,600,000	$ 593,100,000	583,600,000
Contingent interest, minimum trading price per principal amount				$ 1,300
Convertible debt threshold trading days | tradingDay						20
Convertible debt threshold consecutive trading days | tradingDay					30	30
Convertible debt conversion ratio					1.30	1.30	0.0147632
Convertible debt conversion price (in usd per share) | $ / shares					$ 67.74		$ 67.74
Borrowing rates of similar debt without the conversion feature				5.79%
Unamortized debt discount				$ 59,000,000.0	$ 4,644,000	$ 14,363,000	$ 4,644,000	14,363,000
Convertible debt carrying amount of equity component				$ 37,700,000	37,688,000	37,700,000	37,688,000	37,700,000
Effective interest rate				5.81%
If-converted value in excess of the principal amount							$ 173,300,000	154,300,000
Convertible debt remaining discount amortization period							6 months
Debt issuance costs					855,000	2,605,000	$ 855,000	2,605,000
Interest expense							24,546,000	23,852,000	$ 23,198,000
Outstanding debt originating from the Paycheck Protection Program					402,414,000	402,500,000	402,414,000	402,500,000
Convertible Debt | 3.25% Convertible Notes | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Convertible debt threshold trading days | tradingDay				20
Convertible debt threshold consecutive trading days | tradingDay				30
Convertible debt conversion ratio				1.30
Convertible Debt | 3.25% Convertible Notes | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Convertible debt threshold consecutive trading days | tradingDay				10
Convertible debt conversion ratio				0.98
Convertible debt threshold consecutive business days | tradingDay				5
Convertible Debt | 1.75% Convertible Notes
Debt Instrument [Line Items]
Face amount		$ 550,000,000.0
Stated interest rate		1.75%
Proceeds from debt, net of issuance costs		$ 537,100,000
Fair value of senior notes					$ 569,700,000	559,600,000	$ 569,700,000	559,600,000
Convertible debt conversion ratio							0.0079864
Convertible debt conversion price (in usd per share) | $ / shares					$ 125.21		$ 125.21
Borrowing rates of similar debt without the conversion feature		5.50%
Unamortized debt discount		$ 118,900,000			$ 102,631,000	117,193,000	$ 102,631,000	117,193,000
Convertible debt carrying amount of equity component		$ 88,100,000			88,138,000	88,138,000	$ 88,138,000	88,138,000
Effective interest rate		5.50%
Convertible debt remaining discount amortization period							5 years 9 months 18 days
Debt issuance costs		$ 2,800,000			8,889,000	9,987,000	$ 8,889,000	9,987,000
Gross debt issuance costs		12,900,000
Accumulated amortization of debt issuance costs		$ 10,100,000
Unamortized debt issuance expense					8,900,000		8,900,000
Interest expense							25,314,000	3,014,000
Outstanding debt originating from the Paycheck Protection Program					550,000,000	550,000,000	550,000,000	550,000,000
Convertible Debt | 1.75% Convertible Notes | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Convertible debt threshold trading days | tradingDay		20
Convertible debt threshold consecutive trading days | tradingDay		30
Convertible debt conversion ratio		1.30
Convertible Debt | 1.75% Convertible Notes | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Convertible debt threshold trading days | tradingDay		5
Convertible debt threshold consecutive trading days | tradingDay		10
Convertible debt conversion ratio		0.98
Line of Credit | MUFG Credit Facility
Debt Instrument [Line Items]
Proceeds from line of credit								185,000,000.0
Lines of credit paid off								185,000,000.0
Line of credit, debt issuance costs before accumulated amortization					400,000		400,000
Line of credit, debt issuance costs after accumulated amortization						300,000		300,000
Interest expense							0	3,400,000
Loans Payable | Paycheck Protection Program, CARES Act
Debt Instrument [Line Items]
Outstanding debt originating from the Paycheck Protection Program					$ 910,000	$ 0	$ 910,000	$ 0