Pension and Other Postretirement Benefit Plans - Accumulated and Projected Benefit Obligation in Excess of Plan Assets (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
U.S. [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Projected benefit obligation	$ 3,963	$ 764
Fair value of plan assets	3,247	0
Accumulated benefit obligation	810	619
Fair value of plan assets	138	0
International [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Projected benefit obligation	5,513	2,196
Fair value of plan assets	4,341	1,529
Accumulated benefit obligation	2,749	1,871
Fair value of plan assets	$ 1,870	$ 1,424

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=34716465&loc=d3e4179-114921

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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