Postretirement Benefit Plans (Details 12) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Ending Balance	$ 584	$ 524
Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	69	60
Purchases, sales, settlements	15	15
Unrealized gains/(losses)	(10)	4
Realized gains		1
Net transfers		12
Impact on currency	(4)	1
Ending Balance	90	69
Equity securities \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	4	3
Purchases, sales, settlements	(3)	0
Unrealized gains/(losses)	0	0
Realized gains		1
Net transfers		0
Impact on currency	(1)	0
Ending Balance	0	4
Fixed income \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	7	9
Purchases, sales, settlements	(3)	(3)
Unrealized gains/(losses)	(1)	1
Realized gains		0
Net transfers		0
Impact on currency	(1)	0
Ending Balance	4	7
Hedge Funds
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Ending Balance	146	123
Hedge Funds \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	19	20
Purchases, sales, settlements	27	10
Unrealized gains/(losses)	(5)	1
Realized gains		0
Net transfers		12
Impact on currency	(1)	0
Ending Balance	50	19
Private equity
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Ending Balance	19	22
Private equity \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	22	24
Purchases, sales, settlements	(6)	(4)
Unrealized gains/(losses)	(4)	1
Realized gains		0
Net transfers		0
Impact on currency	(1)	1
Ending Balance	19	22
Other \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning Balance	17	4
Purchases, sales, settlements	0	12
Unrealized gains/(losses)	0	1
Realized gains		0
Net transfers		0
Impact on currency	0	0
Ending Balance	$ 17	$ 17

Actual return on plan assets, separately identifying the amount related to assets sold during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(iv)(02)(A)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930

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- Definition

The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(B)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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-Subparagraph (c)(iv)(02)(B)

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- Definition

Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(iv)(02)(C)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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-Name Accounting Standards Codification

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-Subparagraph (c)(iv)(02)(C)

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