Employee Benefit Plans (Expected Gross Benefit Payments) (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2021	$ 674
2022	684
2023	704
2024	722
2025	732
2026-2030	3,781
Other Postretirement Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2021	71
2022	70
2023	68
2024	68
2025	66
2026-2030	$ 314

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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

+ Details

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- Definition

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

+ References

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- Definition

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

+ References

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

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

+ References

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