Employee Postretirement Benefits (Gross Benefit Payments) (Details) $ in Millions	Dec. 31, 2023 USD ($)
Defined Benefit Pension Plans
2020	$ 182
2021	193
2022	191
2023	192
2024	185
2025-2029	918
Other Postretirement Benefit Plans
2020	56
2021	56
2022	56
2023	54
2024	52
2025-2029	$ 227

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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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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