Property and Equipment, Net (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 458	$ 499
Less: Accumulated depreciation and amortization	(281)	(311)
Property and equipment, net	177	188
Depreciation and amortization expense related to property and equipment	41	41	$ 43
Reduction to gross cost and accumulated depreciation for zero net book value assets	90	36
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	113	121
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	109	108
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	236	270
Amortization	$ 29	$ 30	$ 28

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of decrease in accumulated depreciation, depletion and amortization as a result of sale or disposal of property, plant and equipment.

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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