Employee Benefits, Future Benefits Expected to be Paid Under the Pension and Other Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Subsidy Receipts:
2013	$ 13
2014	14
2015	11
2016	11
2017	11
2018-2022	53
Pension Benefits Qualified [Member]
Future Benefit Payments:
2013	838
2014	813
2015	789
2016	785
2017	782
2018-2022	3,454
Pension Benefits Nonqualified [Member]
Future Benefit Payments:
2013	74
2014	69
2015	64
2016	64
2017	59
2018-2022	274
Other benefits [Member]
Future Benefit Payments:
2013	98
2014	100
2015	103
2016	105
2017	106
2018-2022	$ 511

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

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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.

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