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Investment In Non-Marketable Preferred Stock, In Exchange For Receivables

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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Fair value portion of investments accounted under the equity method.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Equity Investments - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Schedule of Equity Method Investments [Line Items]
Equity method investments under fair value option		$ 148.0	$ 300.0
Gains (losses) on equity method investments		(5.0)	(274.0)	$ (17.0)
Proceeds from settlement of loans, including convertible loans		56.0	0.0	0.0
Equity investments in publicly listed companies		96.0	98.0
Equity investments in publicly listed companies		(6.0)	43.0	0.0
Non-marketable equity securities		130.0	151.0
Gains (losses) on non-marketable equity securities (includes NAV)		25.0	(6.0)	(3.0)
Investment in non-marketable preferred stock, in exchange for trade receivables				4.6
Payments to acquire non-marketable preferred stock		11.0	57.0	32.0
Proceeds from sale or liquidation of equity investments		205.0	0.0	0.0
Dividends from equity investments		6.1	7.5	5.2
Financial commitments to investees, off balance sheet		25.6	28.1
Kigen (UK) Limited
Schedule of Equity Method Investments [Line Items]
Non-marketable equity securities		16.4	15.0
Payments to acquire non-marketable preferred stock		1.4
Ampere \| Convertible loans receivable
Schedule of Equity Method Investments [Line Items]
Proceeds from settlement of loans, including convertible loans	$ 39.3
Ampere \| Loans receivable
Schedule of Equity Method Investments [Line Items]
Convertible debt, current		0.0
Convertible debt, noncurrent			33.8
Arduino
Schedule of Equity Method Investments [Line Items]
Proceeds from sale or liquidation of equity investments		50.5
Acetone Limited
Schedule of Equity Method Investments [Line Items]
Gains (losses) on equity method investments		0.0	(20.0)	(15.9)
Equity method investments, fair value		56.5	56.5
Ampere
Schedule of Equity Method Investments [Line Items]
Gains (losses) on equity method investments			(246.4)
Equity method investments, fair value			143.4
Proceeds from sale of equity method investments	$ 143.4
Publicly Listed Companies
Schedule of Equity Method Investments [Line Items]
Equity investments in publicly listed companies		96.1	97.9
Equity investments in publicly listed companies		(5.6)	42.6
Fair Value Measured at Net Asset Value Per Share
Schedule of Equity Method Investments [Line Items]
Equity method investments under fair value option		91.3	100.3
Gains (losses) on equity method investments		(6.7)	(6.0)	(2.8)
Non-marketable equity securities		27.2	15.7
Gains (losses) on non-marketable equity securities (includes NAV)		$ 5.1	$ (2.2)	$ 0.5