Fair Value Measurements - Schedule of Changes in the Fair Value of Level III Financial Instruments - Partnerships and LLC Interests (Details) $ in Thousands	12 Months Ended
Mar. 31, 2026 USD ($) fund	Mar. 31, 2025 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Number of investment funds consolidated \| fund	4
Partnership and LLC interests
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period:	$ 64,530	$ 13,694
Transfers into Level III	0	9,289
Transfers out of Level III	0	(4,332)
Purchases	10,808	38,369
Change in fair value	4,441	7,510
Deconsolidation of fund - Level III derecognition	(77,861)	0
Initial consolidation of funds - Level III recognition	93,896	0
Settlements	(1,918)	0
Balance, end of period:	93,896	64,530
Changes in unrealized gains included in earnings related to financial assets still held at the reporting date	$ 4,441	$ 7,510

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Deconsolidation Of Fund

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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