Employee Benefit Plans (Benefit Payments Expected Future Service) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2013	$ 231
2014	245
2015	255
2016	300
2017	334
2018-2022	1,749
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
2013	89
2014	93
2015	96
2016	100
2017	103
2018-2022	$ 555

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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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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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- Definition

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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- Definition

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

+ References

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- Definition

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

+ References

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