Equity Investments - Schedule of Equity Investments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Mar. 31, 2025
Investments, All Other Investments [Abstract]
Equity method investments under fair value option	$ 294	$ 300
Equity investments in publicly listed companies	94	98
Equity method investments under equity method	17	16
Non-marketable equity securities	151	151
Total equity investments	$ 556	$ 565

Equity Method Investments, Excluding Fair Value Option

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- Definition

Equity Method Investments, Fair Value Option

+ References

No definition available.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) and investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

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- References

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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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