Assets and Liabilities, at Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Parenthetical) (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Jun. 30, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collectible coin inventory, held at lower of cost or net realizable value	$ 102,663	$ 68,193
Liabilities on borrowed metals	916,696	$ 46,051
Not Measured at Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities on borrowed metals	$ 837,400

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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