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

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Long-term Corporate Debt and Borrowing Arrangements (Narrative) (Detail) - USD ($)	1 Months Ended
	Aug. 31, 2021	Mar. 31, 2021	Sep. 30, 2021	Jul. 30, 2021	Apr. 30, 2020
Debt Instrument [Line Items]
Total Capacity			$ 13,509,000,000
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Total Capacity				$ 1,950,000,000	$ 1,800,000,000
5.375% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Amount issued		$ 600,000,000
Debt instrument stated interest percentage		5.375%	5.375%
10.500% Senior Secured Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage		10.50%	10.50%
Repayments of debt		$ 599,000,000
4.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Amount issued		$ 500,000,000
Debt instrument stated interest percentage		4.75%	4.75%
6.375 % Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage		6.375%
Repayments of debt		$ 356,000,000
5.250% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Amount issued			$ 235,000,000
Debt instrument stated interest percentage		5.25%	5.25%
Repayments of debt	$ 239,000,000	$ 142,000,000