Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income tax expense	$ (232)	$ (100)	$ (651)	$ (61)
Effective income tax rate reconciliation, percent	38.80%	42.00%	37.80%	12.30%
Income tax expense related to excess tax benefit on share-based compensation			$ 24