Understanding our Financial Statements and the Impact to the Common Shareholder - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Total revenues	$ (39,125)	$ (7,943)
Provision for credit losses	1,048	1,000
Operating Segments \| Ben Liquidity
Segment Reporting Information [Line Items]
Total revenues	33,421	42,583
Provision for credit losses	0	0
Operating Segments \| Ben Custody
Segment Reporting Information [Line Items]
Total revenues	12,743	21,574
Provision for credit losses	1,047	0
Consolidating Eliminations
Segment Reporting Information [Line Items]
Total revenues	45,571	63,404
Provision for credit losses	71,907	40,693
Consolidating Eliminations \| Ben Liquidity
Segment Reporting Information [Line Items]
Provision for credit losses	71,907	38,886
Financing receivable, credit loss, insurance reimbursable receivables	1,300	800
Loan losses related to fee receivables	1,000	1,800
Loan losses related to notes receivable		1,000
Consolidating Eliminations \| Ben Custody
Segment Reporting Information [Line Items]
Provision for credit losses	$ 0	$ 1,807
Customer ExAlt Trusts
Segment Reporting Information [Line Items]
Recurring fee, percentage	2.80%
Minimum
Segment Reporting Information [Line Items]
Expected life	7 years
Minimum \| Customer ExAlt Trusts
Segment Reporting Information [Line Items]
Interest rate	5.00%
One time fee, percentage	1.00%
Maximum
Segment Reporting Information [Line Items]
Expected life	10 years
Maximum \| Customer ExAlt Trusts
Segment Reporting Information [Line Items]
Interest rate	14.00%
One time fee, percentage	7.00%

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