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Financing and Other Debt - Summary of Outstanding Borrowings (Details) - USD ($)	Dec. 31, 2021	Apr. 01, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 2,905,088,000			$ 3,132,090,000
Current portion of gross debt	165,703,000			170,556,000
Less: Unamortized debt issuance costs/debt discount	(9,934,000)			(17,826,000)
Short-term debt, net	155,769,000			152,730,000
Long-term portion of gross debt	2,739,385,000			2,961,534,000
Less: Unamortized debt issuance costs/debt discount	(44,020,000)			(87,421,000)
Long-term debt, net	2,695,365,000			2,874,113,000
Participation debt
Debt Instrument [Line Items]
Long-term Debt, Gross	1,500,000			0
Borrowed Federal Funds
Debt Instrument [Line Items]
Long-term Debt, Gross	0			20,000,000
Revolving line-of-credit facility under Amended and Restated Credit Agreement \| Amended and Restated Credit Agreemen
Supplemental information under Amended and Restated Credit Agreement:
Remaining borrowing capacity on revolving credit facility	758,808,000	$ 930,000,000	$ 870,000,000	818,372,000
Revolving line-of-credit facility under Amended and Restated Credit Agreement \| Amended and Restated Credit Agreemen \| Letter of Credit
Supplemental information under Amended and Restated Credit Agreement:
Letters of credit	51,392,000			51,628,000
Secured debt
Debt Instrument [Line Items]
Long-term Debt, Gross	100,861,000			85,945,000
Secured debt \| Revolving line-of-credit facility under Amended and Restated Credit Agreement
Debt Instrument [Line Items]
Long-term Debt, Gross	119,800,000			0
Secured debt \| Revolving line-of-credit facility under Amended and Restated Credit Agreement \| Tranche A term loan
Supplemental information under Amended and Restated Credit Agreement:
Letters of credit				0
Secured debt \| Line of Credit \| Amended and Restated Credit Agreemen
Debt Instrument [Line Items]
Long-term Debt, Gross	2,372,927,000			2,316,145,000
Secured debt \| Line of Credit \| Tranche A term loan
Debt Instrument [Line Items]
Long-term Debt, Gross	941,742,000			873,777,000
Secured debt \| Line of Credit \| Tranche B term loan
Debt Instrument [Line Items]
Long-term Debt, Gross	1,431,185,000			1,442,368,000
Senior Notes \| Notes outstanding
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0			400,000,000
Convertible Debt
Debt Instrument [Line Items]
Long-term Debt, Gross				$ 310,000,000