Long-Term Debt - Narrative (Details)				12 Months Ended
	Jun. 14, 2019 USD ($) $ / shares shares	Aug. 01, 2018	Jul. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) trading_day $ / shares $ / unit shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2019 USD ($)	Jun. 03, 2016 USD ($)
Debt Instrument [Line Items]
Unrealized Gain on Derivatives, Tax				$ 397,000	$ (73,000)	$ (320,000)
Debt Instrument, Face Amount				345,000,000			$ 300,000,000.0
Proceeds from issuance of short and long-term debt				$ 489,000,000	607,000,000	15,000,000
Derivative, Number of Instruments Held				3
Derivative, Amount of Hedged Item				$ 150,000,000
Derivative, Fixed Interest Rate				4.70%
Debt Issuance Costs, Gross				$ 7,973,000
Write off of Deferred Debt Issuance Cost					89,000
Loss on extinguishment of debt				0	14,000	0
Repayments of Long-term Debt				$ 443,500,000	320,188,000	101,750,000
Debt Instrument, Interest Rate, Stated Percentage				1.75%
Debt Instrument Additional Principal Amount				$ 45,000,000.0
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger				130.00%
Debt Instrument, Convertible, Threshold Consecutive Trading Days | trading_day				30
Proceeds from Debt, Net of Issuance Costs				$ 334,800,000
Debt Conversion, Converted Instrument, Amount				$ 1,000,000
Debt Conversion, Converted Instrument, Shares Issued | shares				59.8256
Debt Instrument, Convertible, Conversion Price | $ / shares				$ 16.72
Payments for Repurchase of Common Stock	$ 10,000,000			$ 10,000,000	0	$ 9,542,000
Shares Issued, Price Per Share | $ / shares	$ 11.73
Debt Instrument, Interest Rate, Effective Percentage				6.40%
Derivative, Cap Price | $ / unit				23.46
Payments For Capped Call Transactions				$ 28,325,000
Deferred Tax Assets, Convertible Note Hedge				$ 6,772,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased | shares	852,515,000
Credit Facility, 2018 [Member]
Debt Instrument [Line Items]
Repayments of debt			$ 232,000,000
Debt Issuance Costs, Gross			$ 3,376,000
Line of Credit Facility, Interest Rate at Period End				4.56%
Credit Facility, 2018 [Member] | LIBOR Rate Option | Leverage Ratio, Term One | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			2.00%
Credit Facility, 2018 [Member] | LIBOR Rate Option | Leverage Ratio, Term Four | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			2.75%
Credit Facility, 2018 [Member] | Base Rate Option | Federal Funds
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
Credit Facility, 2018 [Member] | Base Rate Option | Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Credit Facility, 2018 [Member] | Base Rate Option | Leverage Ratio, Term One | Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Credit Facility, 2018 [Member] | Base Rate Option | Leverage Ratio, Term Four | Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			1.75%
Revolving Credit Facility | Line of Credit | 2016 Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity								$ 325,000,000
Proceeds from issuance of short and long-term debt					40,000,000
Repayments of Long-term Debt					35,000,000
Revolving Credit Facility | Line of Credit | Credit Facility, 2018 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 500,000,000
Proceeds from issuance of short and long-term debt				$ 144,000,000
Unused capacity, commitment fee, percent		0.30%
Debt Issuance Costs, Gross			2,813,000
Repayments of Long-term Debt				348,500,000	42,000,000
Term Loan | Secured debt | 2016 Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Face Amount								$ 125,000,000
Repayments of Long-term Debt					9,400,000
Term Loan | Secured debt | Credit Facility, 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			100,000,000
Debt Issuance Costs, Gross			$ 474,000
Repayments of Long-term Debt				95,000,000	5,000,000
Accumulated Other Comprehensive Income
Debt Instrument [Line Items]
Unrealized Gain on Derivatives, Tax				(4,000)	393,000
Fair Value, Recurring | Level 2 Assets
Debt Instrument [Line Items]
Interest Rate Derivative Assets, at Fair Value				$ 18,000	$ 1,859,000