Employee Benefit Plans, Benefit Payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Plans [Member]
Estimated Future Benefit Payments
2021	$ 195
2022	227
2023	199
2024	202
2025	215
2026-2030	1,107
Employee Benefit Plans (Textual)
Future employer contributions to pension and other postretirement plans	128
Other Postretirement Benefit Plans [Member]
Estimated Future Benefit Payments
2021	21
2022	21
2023	21
2024	20
2025	20
2026-2030	90
Employee Benefit Plans (Textual)
Future employer contributions to pension and other postretirement plans	$ 22

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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.

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

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

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

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

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

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next 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 (g)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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-Publisher FASB
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Employee Benefit Plans, Textual [Abstract]

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