Pension and Other Postretirement Employee Benefit Plans - Weighted Average Asset Allocation (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
U.S. defined benefit pension plans
Asset category
Target plan asset allocations	100.00%
Actual plan asset allocations	100.00%	100.00%
U.S. defined benefit pension plans \| United States equity securities
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	45.00%
U.S. defined benefit pension plans \| International equity securities
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	40.00%
U.S. defined benefit pension plans \| Debt securities
Asset category
Actual plan asset allocations	31.00%	25.00%
U.S. defined benefit pension plans \| Hedge funds
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	5.00%
U.S. defined benefit pension plans \| Real estate
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	10.00%
Actual plan asset allocations	4.00%	4.00%
U.S. defined benefit pension plans \| Real assets
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	10.00%
U.S. defined benefit pension plans \| Private equity
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	20.00%
U.S. defined benefit pension plans \| Equity securities
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	85.00%
Actual plan asset allocations	46.00%	48.00%
U.S. defined benefit pension plans \| Alternative investments
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	35.00%
Actual plan asset allocations	19.00%	23.00%
Non-U.S. defined benefit pension plans
Asset category
Target plan asset allocations	100.00%
Actual plan asset allocations	100.00%	100.00%
Non-U.S. defined benefit pension plans \| Debt securities
Asset category
Target plan asset allocations	62.00%
Actual plan asset allocations	61.00%	63.00%
Non-U.S. defined benefit pension plans \| Real estate
Asset category
Target plan asset allocations	0.00%
Actual plan asset allocations	0.00%	0.00%
Non-U.S. defined benefit pension plans \| Equity securities
Asset category
Target plan asset allocations	37.00%
Actual plan asset allocations	38.00%	36.00%
Non-U.S. defined benefit pension plans \| Alternative investments
Asset category
Target plan asset allocations	1.00%
Actual plan asset allocations	1.00%	1.00%
OPEB Plans
Asset category
Target plan asset allocations	100.00%
Actual plan asset allocations	100.00%	100.00%
OPEB Plans \| Debt securities
Asset category
Target Allocation, Minimum	30.00%
Target Allocation, Maximum	70.00%
Actual plan asset allocations	50.00%	50.00%
OPEB Plans \| Real estate
Asset category
Target plan asset allocations	0.00%
Actual plan asset allocations	0.00%	0.00%
OPEB Plans \| Equity securities
Asset category
Target Allocation, Minimum	30.00%
Target Allocation, Maximum	70.00%
Actual plan asset allocations	50.00%	50.00%
OPEB Plans \| Alternative investments
Asset category
Target plan asset allocations	0.00%
Actual plan asset allocations	0.00%	0.00%
US Pension Plans and Other US Postretirement Employee Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Amount Of Plan Investments Held In Funds That Are Sponsored Or Managed By Affiliates Of Entity	3,700	2,900
Non-U.S. pension and other postretirement employee benefit plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Amount Of Plan Investments Held In Funds That Are Sponsored Or Managed By Affiliates Of Entity	1,400	242
Debt securities \| U.S. defined benefit pension plans
Asset category
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	80.00%

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For defined benefit and OPEB plans, amount of plan investments held in funds that are sponsored or managed by affiliates of the entity.

+ References

No definition available.

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)

-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)(i)

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

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

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

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