Long-term Corporate Debt and Borrowing Arrangements (Narrative) (Detail) - Senior Notes - USD ($)	1 Months Ended
Mar. 31, 2021	Jun. 30, 2021
5.375% 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
Debt Instrument [Line Items]
Debt instrument stated interest percentage	10.50%	10.50%
Repayments of debt	$ 599,000,000
4.750% Senior Notes
Debt Instrument [Line Items]
Amount issued	$ 500,000,000
Debt instrument stated interest percentage	4.75%	4.75%
6.375 % Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	6.375%
Repayments of debt	$ 356,000,000
5.250% Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.25%	5.25%
Repayments of debt	$ 142,000,000

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

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