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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt Obligations - Senior Unsecured Notes Issuances - Additional Information (Details) - Senior Unsecured Notes [Member] - USD ($) $ in Millions	1 Months Ended
	Feb. 28, 2021	Aug. 31, 2020	Nov. 30, 2019	Jan. 31, 2019	Sep. 01, 2020
Debt Instrument [Line Items]
Interest rate on fixed rate debt	5.125%
Senior Unsecured 6½% Senior Notes due July 2027 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued				$ 750.0
Interest rate on fixed rate debt				6.50%
Maturity date				Jul. 31, 2027
Net proceeds from private placement of notes				$ 1,486.6
Senior Unsecured of 6⅞% Senior Notes due January 2029 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued				$ 750.0
Interest rate on fixed rate debt				6.875%
Maturity date				Jan. 31, 2029
Senior Unsecured 4 1/8% notes due November 2019 [Member]
Debt Instrument [Line Items]
Interest rate on fixed rate debt				4.125%
Senior Unsecured of 5½% Senior Notes due March 2030 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued			$ 1,000.0
Interest rate on fixed rate debt			5.50%
Maturity date			Mar. 31, 2030
Net proceeds from private placement of notes			$ 990.8
Senior Unsecured 4⅞% Notes due February 2031 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued		$ 1,000.0
Interest rate on fixed rate debt		4.875%
Net proceeds from private placement of notes		$ 991.0
Senior Unsecured 6¾% Notes due March 2024 [Member]
Debt Instrument [Line Items]
Interest rate on fixed rate debt		6.75%			6.75%
Senior Unsecured of 4% Senior Notes due 2032 [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued	$ 1,000.0
Interest rate on fixed rate debt	4.00%
Net proceeds from private placement of notes	$ 991.0
Senior Unsecured 5⅛% Notes due 2025 [Member]
Debt Instrument [Line Items]
Interest rate on fixed rate debt	5.125%