Retirement Benefits Estimated Future Benefit Payments (Details 8) $ in Millions	Dec. 31, 2019 USD ($)
Estimated Benefit Payments (Table Amounts) [Abstract]
2020	$ 2,000
2021	2,048
2022	2,086
2023	2,129
2024	2,175
2025 through 2029	11,332
Pension Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2020	1,849
2021	1,898
2022	1,947
2023	1,991
2024	2,039
2025 through 2029	10,702
Medical and Life Benefits
Estimated Benefit Payments (Table Amounts) [Abstract]
2020	151
2021	150
2022	139
2023	138
2024	136
2025 through 2029	$ 630

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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=118255775&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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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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

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