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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Stock-Based Compensation (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4	$ 7	$ 2	$ 12
Stock-based compensation expense (net of tax)	$ 2	$ 5	$ 1	$ 9
Senior Notes [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Debt Instrument, Maturity Date, Description			July 2027
Ten and One over Two Euro-Denominated Senior Notes \| Senior Notes [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Debt Instrument, Maturity Date, Description			May 2025