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Interest Expense - Narrative (Details) - USD ($) $ in Thousands				1 Months Ended	12 Months Ended
	Dec. 22, 2020	Dec. 20, 2019	Feb. 13, 2019	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Feb. 12, 2018
Debt Instrument [Line Items]
Subordinated Borrowing, Interest Rate	4.625%
Effective interest rate, revolving credit facility					4.50%	5.30%	6.02%
Repayments of Secured Debt					$ 896,214	$ 350,140	$ 56,372
Accelerated Accretion Expense					5,340	2,196	1,455
Accelerated Amortization of Debt Issuance Costs					9,179	4,125	3,476
Redemption Premium					0	0	4,782
Accretion Expense on Extinguished Debt					0	0	$ 19,414
Accelerated Accretion						18,700
Accelerated Amortization of Debt Issuance Costs						$ 300
Old Revolving Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End								4.56%
Old Term Loan Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End								4.58%
2012 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage								6.375%
2018 Term Loan Facility [Member]
Debt Instrument [Line Items]
Repayments of Secured Debt		$ 225,000	$ 125,000		820,000
Secured Debt
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 500,000	$ 500,000
Senior Subordinated Notes [Member] | 2018 Term Loan Facility [Member]
Debt Instrument [Line Items]
Repayments of Secured Debt				500,000
Accelerated Accretion Expense				3,200
Accelerated Amortization of Debt Issuance Costs				$ 5,200

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Face (par) amount of debt instrument at time of issuance.

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