Retirement Benefits (Details 8) $ in Millions	Dec. 31, 2018 USD ($)
Estimated Benefit Payments (Table Amounts) [Abstract]
2019	$ 1,934
2020	1,989
2021	2,022
2022	2,069
2023	2,109
2024 through 2028	11,035
Pension Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2019	1,781
2020	1,834
2021	1,880
2022	1,928
2023	1,970
2024 through 2028	10,384
Medical and Life Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2019	153
2020	155
2021	142
2022	141
2023	139
2024 through 2028	$ 651

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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