Stockholders' Equity (Narrative) (Detail) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) shares	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) shares	Jun. 30, 2018 USD ($) shares	Aug. 01, 2019 USD ($)
Stockholders Equity [Line Items]
Currency translation adjustments (net of tax of $4, $(10), $(2), and $(5) respectively)	$ 9	$ (54)	$ 10	$ (53)
Stock Repurchased During Period, Shares | shares				1.6
Stock Repurchased During Period, Value				$ 67
Other Comprehensive Income Unrealized Gain Loss On Cash Flow Hedges Arising During Period Net Of Tax			(19)	8
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax			(2)	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax			(21)	8
Stock Repurchase Program, Authorized Amount	1,700		1,700
Stock Repurchase Program, Remaining Authorized Repurchase Amount	150		150
Option Premiums Paid	$ 16		$ 16
Temporary Equity, Shares Outstanding | shares	0.6		0.6
Selling, General and Administrative Expenses [Member]
Stockholders Equity [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	$ 2	2	$ 4	4
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax	$ 2	$ 1	$ 3	$ 2
Subsequent Event [Member]
Stockholders Equity [Line Items]
Stock Repurchase Program, Authorized Amount					$ 100