Pension and Other Postemployment Benefits (Details 9) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Pensions
Estimated Future Benefit Payments
2015	$ 467
2016	476
2017	491
2018	513
2019	529
2020-2024	2,887
OPEB \| Employer Subsidized Benefit
Estimated Future Benefit Payments
2015	59
2016	59
2017	58
2018	56
2019	55
2020-2024	260
OPEB \| Medicare Rx Reimbursement
Estimated Future Benefit Payments
2015	(3)
2016	(3)
2017	(3)
2018	(3)
2019	(3)
2020-2024	$ (10)

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (f)

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

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Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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+ References

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+ References

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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+ References

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