Postretirement Benefit Plans - Employer Contributions to Plans (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Contributions to employee benefit plans
Funded pension plans	$ 0	$ 19	$ 23	$ 21
Unfunded pension plans	4	3	8	7
Savings and defined contribution pension plans	14	14	32	30
Total contributions	$ 18	$ 36	$ 63	$ 58

Defined contribution plan employers contribution to funded pension plan.

No definition available.

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- Definition

Defined contribution plan employers contribution to savings and defined contribution pension plan.

+ References

No definition available.

+ Details

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- Definition

Defined contribution plan employer's contribution to unfunded pension plan.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (g)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-25

+ Details

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