Pension and Other Postemployment Benefits (Details 9) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pensions
Estimated Future Benefit Payments
2013	$ 439
2014	473
2015	486
2016	496
2017	505
2018-2022	2,687
OPEB \| Employer Subsidized Benefit
Estimated Future Benefit Payments
2013	157
2014	127
2015	68
2016	68
2017	68
2018-2022	337
OPEB \| Medicare Rx Reimbursement
Estimated Future Benefit Payments
2013	(3)
2014	(3)
2015	(3)
2016	(3)
2017	(3)
2018-2022	$ (13)

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ 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=21915506&loc=d3e1928-114920

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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