Financing and Other Debt - Schedule of Debt (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,855,164,000	$ 2,972,674,000
Current portion of gross debt	155,172,000	256,529,000
Less: Unamortized debt issuance costs/debt discount	(7,953,000)	(7,998,000)
Short-term debt, net	147,219,000	248,531,000
Long-term portion of gross debt	2,699,992,000	2,716,145,000
Less: Unamortized debt issuance costs/debt discount	(27,657,000)	(29,632,000)
Long-term debt, net	2,672,335,000	2,686,513,000
Supplemental information under 2016 Credit Agreement:
Letters of credit	51,300,000	51,314,000
Remaining borrowing capacity on revolving credit facility	768,700,000	768,686,000
2016 Credit Agreement
Supplemental information under 2016 Credit Agreement:
Letters of credit	2,400,000,000
Participation debt
Debt Instrument [Line Items]
Long-term debt, gross	0	50,000,000
Borrowed federal funds
Debt Instrument [Line Items]
Long-term debt, gross	0	34,998,000
Secured debt
Debt Instrument [Line Items]
Long-term debt, gross	88,176,000	104,261,000
Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	0	35,000,000.0
Line of Credit \| Secured debt \| 2016 Credit Agreement
Debt Instrument [Line Items]
Long-term debt, gross	2,364,603,000	2,380,755,000
Line of Credit \| Secured debt \| Tranche A term loan
Debt Instrument [Line Items]
Long-term debt, gross	911,225,000	923,707,000
Line of Credit \| Secured debt \| Tranche B term loan
Debt Instrument [Line Items]
Long-term debt, gross	1,453,378,000	1,457,048,000
Notes payable \| Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	$ 400,000,000	$ 400,000,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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