Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	$ 821	$ 787
Accumulated Amortization	502	414
Net Carrying Value	319	373
Indefinite-lived Intangible Assets (Excluding Goodwill) [Abstract]
Intangible assets, gross	1,011	977
Net Carrying Value	509	563
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	619
Accumulated Amortization	365	305
Net Carrying Value	254	314
Software
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	202	168
Accumulated Amortization	137	109
Net Carrying Value	$ 65	$ 59

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 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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