Retirement Benefits (Details 11) $ in Millions	Dec. 31, 2015 USD ($)
Estimated Benefit Payments (Table Amounts) [Abstract]
2016	$ 1,620
2017	1,668
2018	1,721
2019	1,774
2020	1,825
2021 through 2025	9,853
Pension Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2016	1,469
2017	1,513
2018	1,563
2019	1,614
2020	1,664
2021 through 2025	9,065
Medical and Life Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2016	151
2017	155
2018	158
2019	160
2020	161
2021 through 2025	$ 788

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- Definition

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=58740216&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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Amount of benefits from a defined benefit plan expected to be paid in 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

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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.

+ 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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