Income Taxes (Components of Income Tax Expense) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current income tax expense
U.S. federal	$ 182	$ (251)	$ 132
U.S. State and local	49	(12)	20
Non-U.S.	349	306	261
Total current income tax	580	43	413
Deferred income tax expense
U.S. federal	105	176	31
U.S. State and local	(16)	(10)	6
Non-U.S.	(53)	8	(37)
Deferred Income Tax Expense (Benefit)	36	174	0
Total	$ 616	$ 217	$ 413