Goodwill and Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2025	Mar. 31, 2024
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	$ 787	$ 738
Accumulated Amortization	414	327
Net Carrying Value	373	411
Indefinite-lived Intangible Assets (Excluding Goodwill) [Abstract]
Intangible assets, gross	977	928
Net Carrying Value	563	601
Trade name
Indefinite-lived Intangible Assets (Excluding Goodwill) [Abstract]
Unamortizable intangible assets	190	190
Customer contracts and related customer relationships
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	619	592
Accumulated Amortization	305	238
Net Carrying Value	314	354
Software
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	168	146
Accumulated Amortization	109	89
Net Carrying Value	$ 59	$ 57

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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