Income Taxes (Unrecognized Tax Benefits) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 3,000	$ 3,400
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	148	94	$ 82
Current year tax positions - additions	36	37	25
Prior year tax positions - additions	17	26	8
Prior year tax positions - reductions	(6)	0	(11)
Statute of limitations expirations	(9)	(8)	(8)
Settlements	(15)	(10)	0
Foreign currency translation	(5)	9	(2)
Ending balance	$ 166	$ 148	$ 94