Stockholders' Equity - Changes in Each Component of AOCI of the Parent (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		$ (1,174)
Other comprehensive income (loss):
Other comprehensive income (loss) attributable to the parent company		41	$ (83)
Balance,		(1,133)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(608)	(427)
Other comprehensive income (loss):
Currency translation adjustments		29	(101)
Holding gains and losses on net investment hedge			2
Other comprehensive income (loss) attributable to the parent company		29	(99)
Balance,		(579)	(526)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(4)	(9)
Other comprehensive income (loss):
Holding gains and losses		1	(6)
Reclassification of amount to net income	[1]	2	5
Other comprehensive income (loss) attributable to the parent company		3	(1)
Balance,		(1)	(10)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		2	5
Other comprehensive income (loss):
Holding gains and losses		$ 2	$ 1
Reclassification of amount to net income	[1]
Other comprehensive income (loss) attributable to the parent company		$ 2	$ 1
Balance,		4	6
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(564)	(566)
Other comprehensive income (loss):
Reclassification adjustment for net actuarial losses included in net periodic benefit cost	[2]	7	6
Elimination of net prior service costs and actuarial losses of disposal group			10
Other comprehensive income (loss) attributable to the parent company		7	16
Balance,		(557)	(550)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(1,174)	(997)
Other comprehensive income (loss):
Currency translation adjustments		29	(101)
Holding gains and losses on net investment hedge			2
Holding gains and losses		3	(5)
Reclassification of amount to net income	[1]	2	5
Reclassification adjustment for net actuarial losses included in net periodic benefit cost	[2]	7	6
Elimination of net prior service costs and actuarial losses of disposal group			10
Other comprehensive income (loss) attributable to the parent company		41	(83)
Balance,		$ (1,133)	$ (1,080)

[1] Foreign currency contract and investment reclassifications are included in other income, net.

[2] See Note 9 for additional details.