Stockholders' Equity - Changes in Each Component of AOCI of the Parent (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,				$ (1,174)
Other comprehensive income (loss):
Other comprehensive loss attributable to the parent company		$ (24)	$ (53)	(13)	$ (113)
Balance,		(1,187)		(1,187)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(603)	(512)	(608)	(427)
Other comprehensive income (loss):
Currency translation adjustments		(8)	(66)	(3)	(149)
Holding gains and losses on net investment hedge					(2)
Tax expense
Other comprehensive loss attributable to the parent company		(8)	(66)	(3)	(151)
Balance,		(611)	(578)	(611)	(578)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(14)	(7)	(4)	(9)
Other comprehensive income (loss):
Holding gains and losses		(17)	(4)	(30)	(13)
Reclassification of amount to net income	[1]	6	5	9	16
Tax expense
Other comprehensive loss attributable to the parent company		(11)	1	(21)	3
Balance,		(25)	(6)	(25)	(6)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		5	5	2	5
Other comprehensive income (loss):
Holding gains and losses		2	(5)	5	(5)
Reclassification of amount to net income	[1]	(7)		(7)
Tax expense
Other comprehensive loss attributable to the parent company		(5)	(5)	(2)	(5)
Balance,		0	0	0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(551)	(543)	(564)	(566)
Other comprehensive income (loss):
Actuarial gain (loss) on census update		(6)	13	(6)	13
Reclassification adjustment for net actuarial losses included in net periodic benefit cost	[2]	7	5	20	18
Elimination of net prior service costs and actuarial losses of disposal group					10
Tax expense		(1)	(1)	(1)	(1)
Other comprehensive loss attributable to the parent company		0	17	13	40
Balance,		(551)	(526)	(551)	(526)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance,		(1,163)	(1,057)	(1,174)	(997)
Other comprehensive income (loss):
Currency translation adjustments		(8)	(66)	(3)	(149)
Holding gains and losses on net investment hedge					(2)
Holding gains and losses		(15)	(9)	(25)	(18)
Reclassification of amount to net income	[1]	(1)	5	2	16
Actuarial gain (loss) on census update		(6)	13	(6)	13
Reclassification adjustment for net actuarial losses included in net periodic benefit cost	[2]	7	5	20	18
Elimination of net prior service costs and actuarial losses of disposal group					10
Tax expense		(1)	(1)	(1)	(1)
Other comprehensive loss attributable to the parent company		(24)	(53)	(13)	(113)
Balance,		$ (1,187)	$ (1,110)	$ (1,187)	$ (1,110)

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

[2] See Note 9 for additional details.