Accumulated Other Comprehensive Income (Loss) (AOCI) - Changes in Accumulated Other Comprehensive Income (Loss) (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	$ (205)
Other comprehensive (loss) income before reclassifications	22
Amounts reclassified from AOCI	(4)
Net current period other comprehensive (loss) income	18
Accumulated other comprehensive income (loss), ending balance	(187)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	(224)
Other comprehensive (loss) income before reclassifications	24
Amounts reclassified from AOCI	0
Net current period other comprehensive (loss) income	24
Accumulated other comprehensive income (loss), ending balance	(200)
Changes in Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	6
Other comprehensive (loss) income before reclassifications	0
Amounts reclassified from AOCI	(2)
Net current period other comprehensive (loss) income	(2)
Accumulated other comprehensive income (loss), ending balance	4
Changes in Fair Value of Effective Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated other comprehensive income (loss), beginning balance	13
Other comprehensive (loss) income before reclassifications	(2)
Amounts reclassified from AOCI	(2)
Net current period other comprehensive (loss) income	(4)
Accumulated other comprehensive income (loss), ending balance	$ 9

Accumulated Other Comprehensive Income (Loss) [Roll Forward]

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 31
-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=51821188&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
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Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

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