Postretirement Benefit Plans (Future Benefit Payments) (Details) $ in Millions	Mar. 31, 2026 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2027	$ 105
2028	116
2029	111
2030	116
2031	109
2032 through 2036	547
Total	1,104
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
2027	9
2028	9
2029	9
2030	9
2031	9
2032 through 2036	49
Total	$ 94

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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 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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