Employee Benefit Plans (Expected Gross Benefit Payments) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2020	$ 649
2021	658
2022	670
2023	688
2024	711
2025-2029	3,690
Other Postretirement Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2020	78
2021	74
2022	73
2023	72
2024	74
2025-2029	$ 361

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- Definition

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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- Definition

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 fourth 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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