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- Definition

Goodwill, Impairment Loss, Long-Term Growth Rate

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

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Value of input used to measure derivative asset.

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Amount of accumulated impairment loss for asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Amount of fair value of reporting unit in excess of carrying amount.

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- Definition

Revenues from operations, excluding interest and dividend income. Includes revenues from the following sources: investment banking (underwriting and financial advisory), principal transactions (sales and trading, and investment gains and losses), commissions, asset management, and investment advisory and other services.

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Fair Value Measurements - Narrative (Details)	12 Months Ended
Fair Value Measurements - Narrative (Details)	Mar. 31, 2026 USD ($) $ / shares	Mar. 31, 2025 USD ($) $ / shares	Oct. 15, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative assets	$ 162,824,000	$ 259,113,000
Investment income (loss), net	(49,532,000)	(6,500,000)
Loss on impairment of goodwill and intangible assets	0	3,692,000
Impairment	3,100,000
Goodwill, impairment, accumulated impairment loss	$ 2,400,000,000
Long-term growth rate	3.00%
Ben Custody
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loss on impairment of goodwill and intangible assets	$ 0	3,427,000
Reporting unit, amount of fair value in excess of carrying amount	4,300,000
Ben Markets
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loss on impairment of goodwill and intangible assets	0	$ 265,000
Reporting unit, amount of fair value in excess of carrying amount	$ 1,400,000
Measurement Input, Expected Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.75		2.2
Measurement Input, Share Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	3.50		4.13
Measurement Input, Exercise Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	4.16		4.16
Measurement Input, Price Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.9559		0.3466
Measurement Input, Expected Dividend Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.000		0.000
Measurement Input, Risk Free Interest Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.0367		0.0334
Yorkville \| Measurement Input, Share Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input \| $ / shares	3.50	2.48
Yorkville \| Measurement Input, Exercise Price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input \| $ / shares	21.04	21.04
Yorkville \| Measurement Input, Price Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input \| $ / shares	0.9559	0.901
Yorkville \| Measurement Input, Expected Dividend Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	0.000	0.000
Yorkville \| Measurement Input, Risk Free Interest Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	0.0367	0.0370
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rates	28.00%
Minimum \| Yorkville \| Measurement Input, Expected Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	1.35	2.35
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rates	29.30%
Maximum \| Yorkville \| Measurement Input, Expected Term
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt instrument, measurement input	1.62	2.62