Retirement Benefits - Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2022 USD ($)
Pension Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	$ 805
2024	775
2025	789
2026	790
2027	798
2028 through 2032	3,983
Total estimated future benefits payments through 2032	7,940
Other Postretirement Benefit Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2023	152
2024	152
2025	152
2026	152
2027	153
2028 through 2032	744
Total estimated future benefits payments through 2032	$ 1,505

The total amount of the benefits expected to be paid in the future.

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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 https://asc.fasb.org/extlink&oid=123447040&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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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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