Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2025	Mar. 31, 2025
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	$ 796	$ 787
Accumulated Amortization	437	414
Net Carrying Value	359	373
Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract]
Intangible assets, gross	986	977
Net Carrying Value	549	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	320	305
Net Carrying Value	299	314
Software
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	177	168
Accumulated Amortization	117	109
Net Carrying Value	$ 60	$ 59

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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 40
-SubTopic 30
-Topic 350
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-URI https://asc.fasb.org/1943274/2147482640/350-30-55-40

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 40
-SubTopic 30
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-URI https://asc.fasb.org/1943274/2147482640/350-30-55-40

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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

+ References

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
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-Paragraph 40
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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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