Commitments and Contingencies (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Sep. 30, 2024	Mar. 31, 2026	Mar. 31, 2025
Concentration Risk [Line Items]
Provision for claimed costs		$ 248	$ 245
Amount awarded from other party	$ 115
U.S. Government Contracts
Concentration Risk [Line Items]
Provision for claimed costs		0	0
Claimed Indirect Costs
Concentration Risk [Line Items]
Provision for claimed costs		248	245
Financial Standby Letter of Credit
Concentration Risk [Line Items]
Guarantor obligations, carrying value		3	4
Guarantor obligations, reduction to available borrowings		1	1
Guarantor obligations, facility		3	$ 3
Guarantor obligations, available amount		$ 1

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Guarantor Obligations, Facility

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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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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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- Definition

Indicates, if estimable, the approximate extent to which the proceeds from liquidation of any assets held either as collateral or by third parties would be expected to cover the maximum potential amount of future payments under the guarantee or each group of similar guarantees.

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Amount awarded from other party in judgment or settlement of litigation.

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- Definition

Amount of loss contingency liability.

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