Annual report [Section 13 and 15(d), not S-K Item 405]

MARGIN LENDING, BROKERAGE AND OTHER RECEIVABLES, NET - Narrative (Details)

v3.26.1
MARGIN LENDING, BROKERAGE AND OTHER RECEIVABLES, NET - Narrative (Details)
$ in Thousands
Mar. 31, 2026
USD ($)
Mar. 31, 2025
USD ($)
customer
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Collateral received, fair value $ 8,595,822 $ 6,379,368
Total margin lending, brokerage and other receivables, net 4,690,782 3,319,145
Allowance for receivables 19,959 19,256
Margin lending receivables    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Total margin lending, brokerage and other receivables, net 4,632,506 $ 3,294,569
Nonrelated Party    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Number of customers with a margin lending balance exceeding ten percent | customer   3
Collateralized financings 4,677,913 $ 3,218,277
Nonrelated Party | Margin lending receivables    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Total margin lending, brokerage and other receivables, net $ 3,286,545 $ 2,323,461