Retirement Benefits (Details 10) $ in Millions	Dec. 31, 2016 USD ($)
Estimated Benefit Payments (Table Amounts) [Abstract]
2017	$ 1,681
2018	1,729
2019	1,774
2020	1,823
2021	1,871
2022 through 2026	9,982
Pension Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2017	1,531
2018	1,575
2019	1,622
2020	1,670
2021	1,718
2022 through 2026	9,251
Medical and Life Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2017	150
2018	154
2019	152
2020	153
2021	153
2022 through 2026	$ 731

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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=65897934&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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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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