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Equity Investments - Schedule of Equity Investments (Details) - USD ($) $ in Millions | Jun. 30, 2026 | Mar. 31, 2026
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Investments, All Other Investments [Abstract] |  |
Equity method investments under fair value option | $ 141 | $ 148
Equity investments in publicly listed companies | 290 | 96
Equity method investments under equity method | 12 | 13
Non-marketable equity securities | 146 | 130
Total equity investments | $ 589 | $ 387

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