Stockholders' Equity (Narrative) (Detail) - USD ($) shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Stockholders Equity [Line Items]
Currency translation adjustments (net of tax of $9, $3, $29 and $7, respectively)	$ 32,000,000	$ 20,000,000	$ 105,000,000	$ 100,000,000
Proceeds from Issuance of Preferred Stock, Preference Stock, and Warrants			$ 90
Document Period End Date			Sep. 30, 2017
Document Fiscal Year Focus			2017
Other Comprehensive Income Unrealized Gain Loss On Cash Flow Hedges Arising During Period Net Of Tax			$ (2,000,000)	(7,000,000)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax			2,000,000	3,000,000
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax			0	$ (4,000,000)
Stock Repurchase Program, Authorized Amount	1,500,000,000		$ 1,500,000,000
Stock Repurchased During Period, Shares			4.2	9.5
Stock Repurchased During Period, Value			$ 127,000,000	$ 290,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	174,000,000		174,000,000
Selling, General and Administrative Expenses [Member]
Stockholders Equity [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	2,000,000	1,000,000	6,000,000	4,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax	$ 1,000,000	$ 1,000,000	$ 4,000,000	$ 3,000,000