Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax	$ 2	$ 5	$ 2
Beginning Balance	(2,057)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(292)	542	(299)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	129	(295)	(135)
Net change	(147)	316	336
Ending Balance	(2,300)	(2,057)
Reclassifications of Temporary to Permanent Equity	0
Unrealized Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(1,567)	(1,798)	(1,332)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	(292)	542	(299)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	148	(311)	(167)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0
Net change		231	(466)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(144)
Ending Balance	(1,734)	(1,567)	(1,798)
Reclassifications of Temporary to Permanent Equity	23
Pension and Other Post retirement Benefit Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(493)	(571)	(1,379)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(12)	20	29
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	21	58	779
Net change	9	78	808
Ending Balance	(568)	(493)	(571)
Reclassifications of Temporary to Permanent Equity	84
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassifications of Temporary to Permanent Equity	0
Accumulated Other Comprehensive (Loss)/Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net change	(136)	299	346
Reclassifications of Temporary to Permanent Equity	107
Unrealized Gain (Loss) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	3	13	9
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(7)	(4)	3
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	6	(6)	1
Net change	(1)	(10)	4
Ending Balance	2	3	13
Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(2,057)	(2,356)	(2,702)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	27	52	780
Net change	(136)	299	346
Ending Balance	(2,300)	$ (2,057)	$ (2,356)
Reclassifications of Temporary to Permanent Equity	$ 0