Postretirement Benefit Plans (Future Benefit Payments) (Details) $ in Millions	Mar. 31, 2025 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2026	$ 109
2027	116
2028	114
2029	117
2030	118
2031 through 2035	572
Total	1,146
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2026	8
2027	9
2028	9
2029	9
2030	10
2031 through 2035	58
Total	$ 103

Defined Benefit Plan, Expected Future Benefit Payment

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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

No definition available.

+ Details

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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
-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

+ 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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- Definition

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

+ References

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- Definition

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

+ References

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