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Long-term Corporate Debt and Borrowing Arrangements (Schedule Of Long-Term Debt) (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Other	$ 23		$ 24
Deferred financing fees	(46)		(48)
Total	4,298		4,210
Less: Short-term debt and current portion of long-term debt	21		19
Long-term debt	$ 4,277		4,191
6.375% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	6.375%
Long-term debt	$ 0		350
4.125% euro-denominated Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.125%
Long-term debt	$ 356		366
5.250% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.25%	5.25%
Long-term debt	$ 235		375
4.500% euro-denominated Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.50%
Long-term debt	$ 296		305
10.500% Senior Secured Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	10.50%	10.50%
Long-term debt	$ 0		487
4.750% euro-denominated Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.75%
Long-term debt	$ 415		428
5.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.75%
Long-term debt	$ 726		724
4.750% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.75%	4.75%
Long-term debt	$ 500		0
5.375% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.375%	5.375%
Long-term debt	$ 600		0
Floating Rate Term Loan \| Loans Payable
Debt Instrument [Line Items]
Long-term debt	$ 1,193		$ 1,199
Aggregate interest rate	2.36%
Floating Rate Term Loan \| Interest rate swaps \| Loans Payable
Debt Instrument [Line Items]
Amount of hedged item	$ 700
Aggregate rate	4.58%
Floating Rate Term Loan \| London Interbank Offered Rate (LIBOR) \| Loans Payable
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%