Employee Benefit Plans - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Benefits
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity
2021	$ 1,280
2022	1,270
2023	1,270
2024	1,270
2025	1,270
2026-2030	6,210
Other Postretirement and Postemployment Benefits
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity
2021	340
2022	370
2023	410
2024	430
2025	430
2026-2030	$ 2,110

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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

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- Definition

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

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- Definition

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

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- Definition

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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