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Debt (Narrative) (Details)					3 Months Ended	6 Months Ended
Debt (Narrative) (Details)	Jun. 10, 2022 USD ($)	Sep. 16, 2021	Oct. 07, 2020 USD ($) fiscalQuarterPeriod	Nov. 15, 2019 USD ($) tradingDay	Jun. 30, 2022 USD ($) $ / shares	Jun. 30, 2022 USD ($) $ / shares	Jun. 30, 2021 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)	Apr. 07, 2021 USD ($)
Debt Instrument [Line Items]
Cash tender offer (maximum)					$ 90,000,000
Loss on extinguishment of debt						$ 1,393,000	$ 0
Unamortized discount					3,581,000	3,581,000			$ 91,593,000
Deferred issuance costs					9,391,000	9,391,000			9,056,000
Proceeds from issuance of secured debt					90,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity										$ 100,000,000
Increase available										250,000,000
Total aggregate commitment										$ 350,000,000
Long-term line of credit					$ 0	$ 0			0
4.625% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate			4.625%		4.625%	4.625%
Percentage principal outstanding to be eligible for redemption			50.00%
Covenant, leverage ratio, minimum			3.5
Covenant restricted payment threshold			$ 250,000,000
Covenant, EBITDA minimum			50.00%
Covenant, EBITDA minimum, fiscal quarter period \| fiscalQuarterPeriod			4
Extinguishment of debt, principle amount					$ 21,500,000	$ 76,100,000
Cash tender offer (maximum)					18,200,000	73,600,000
Loss on extinguishment of debt					3,100,000	1,900,000
Fair value of debt instruments					$ 482,500,000	$ 482,500,000			659,900,000
Debt instrument, face amount			$ 750,000,000
Proceeds from debt, net of issuance costs			$ 742,700,000
4.625% Senior Notes \| Senior Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Percentage of principal amount redeemed			40.00%
Redemption price, percentage			104.625%
4.625% Senior Notes \| Senior Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Redemption price, percentage			100.00%
1.75% Convertible Notes \| Convertible Debt
Debt Instrument [Line Items]
Stated interest rate				1.75%	1.75%	1.75%		1.75%
Convertible debt conversion ratio						0.0079864
Preferred stock, convertible, conversion ratio					0.0093783	0.0093783
Fair value of debt instruments					$ 532,500,000	$ 532,500,000			$ 685,400,000
Debt instrument, face amount				$ 550,000,000
Proceeds from debt, net of issuance costs				537,100,000
Convertible debt conversion price (in usd per share) \| $ / shares					$ 106.63	$ 106.63
Gross debt issuance costs				12,900,000
Accumulated amortization of debt issuance costs				10,100,000
Deferred issuance costs				$ 2,800,000
Unamortized debt issuance expense					$ 8,300,000	$ 8,300,000
1.75% Convertible Notes \| Convertible Debt \| Cumulative Effect, Period of Adoption, Adjustment
Debt Instrument [Line Items]
Unamortized discount								$ 87,300,000
1.75% Convertible Notes \| Convertible Debt \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Convertible debt threshold trading days \| tradingDay				20
Convertible debt threshold consecutive trading days \| tradingDay				30
Percentage of stock price				130.00%
1.75% Convertible Notes \| Convertible Debt \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Convertible debt threshold trading days \| tradingDay				5
Convertible debt threshold consecutive trading days \| tradingDay				10
Percentage of product of stock price and conversion rate				98.00%
6.0% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate			6.00%
Bridge Loan Facility \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate						0.50%
Bridge Loan Facility \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate						1.25%
Bridge Loan Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate						1.50%
Bridge Loan Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate						2.25%
Bridge Loan Facility \| Bridge Loan \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		1.00%
Calculation denominator		1.00
Bridge Loan Facility \| Bridge Loan \| Federal Funds Effective Rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Revolving Credit Facility \| Secured Debt
Debt Instrument [Line Items]
Loss on extinguishment of debt					$ (500,000)
Debt instrument, face amount	$ 90,000,000
Credit Agreement \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount	$ 90,000,000
Maturity date, period after funding date	60 days
Credit Agreement \| Line of Credit \| Secured Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Credit Agreement \| Line of Credit \| Secured Debt \| Federal Funds Effective Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%