Fair Value Measurements - Assets and Liabilities at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Mar. 31, 2024
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Public equity securities	$ 334,278	$ 329,119
Debt securities available-for-sale	1,849	2,962
Convertible debt	2,667	0
Warrants liability	648	178
Prepaid forward liability		14
Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible debt	0
Warrants liability	190	178
Prepaid forward liability		14
Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible debt	0
Warrants liability	458	0
Prepaid forward liability		0
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible debt	2,667
Warrants liability	0	0
Prepaid forward liability		0
Public equity securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Public equity securities	4,466	4,897
Public equity securities \| Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Public equity securities	4,466	4,897
Public equity securities \| Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Public equity securities	0	0
Public equity securities \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Public equity securities	0	0
Other equity interests
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other equity interests	12	558
Other equity interests \| Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other equity interests	0	0
Other equity interests \| Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other equity interests	12	558
Other equity interests \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other equity interests	0	0
Debt securities available-for-sale, other
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale	1,849	2,962
Debt securities available-for-sale, other \| Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale	0	0
Debt securities available-for-sale, other \| Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale	0	998
Debt securities available-for-sale, other \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available-for-sale	$ 1,849	$ 1,964

Forward Liability, Fair Value Disclosure

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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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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The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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