Retirement Benefits (Details 11) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
Pension Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2015	$ 1,395
2016	1,452
2017	1,506
2018	1,565
2019	1,623
2020 through 2024	8,975
Medical and Life Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2015	154
2016	158
2017	161
2018	164
2019	166
2020 through 2024	$ 828

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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.

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+ References

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

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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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