Retirement Plans (Schedule of Benefits to be Paid From Retirement Plans Over the Next 10 Years) (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension Benefits
Compensation And Retirement Disclosure Line Items
2021	$ 887
2022	912
2023	935
2024	961
2025	981
2026-2030	5,094
Other Post-retirement Benefits
Compensation And Retirement Disclosure Line Items
2021	64
2022	63
2023	62
2024	60
2025	59
2026-2030	$ 273

Compensation And Retirement Disclosure Line Items

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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

+ Details

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- Definition

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

+ References

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- Definition

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.

+ References

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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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