Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Decrease in valuation allowance	$ 32
Adjustment to additional paid-in-capital for income tax benefits attributable to employee stock compensation	4	$ (126)	$ (89)
Deferred tax liabilities from undistributed foreign earnings	11
Undistributed foreign earnings	2,300
Benefit realized from tax holiday granted	$ 46	$ 23	$ 7
Earnings per share impact of tax holiday	$ 0.17	$ 0.08	$ 0.02
Unrecognized tax benefits that would impact effective tax rate	$ 240	$ 200	$ 174
Accrued potential interest and penalties	15	2	4
Liability recorded for interest and penalties	48	$ 33	$ 31
U.S. Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	126
U.S. State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 110