Income Taxes - Components of Income Tax Table (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current [Abstract]
Federal	$ (177)	$ 188	$ 113
State	(18)	2	42
Foreign	495	1,574	873
Total	300	1,764	1,028
Deferred [Abstract]
Federal	(2,929)	(389)	94
State	(145)	27	(9)
Foreign	(103)	215	52
Total	(3,177)	(147)	137
Total income tax expense (benefit)	$ (2,877)	$ 1,617	$ 1,165