Assets and Liabilities, at Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Parenthetical) (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collectible coin inventory, held at lower of cost or net realizable value	$ 104,512	$ 91,339
Collectible coin and Minting & Refining inventory, held at lower of cost or net realizable value	$ 118,800

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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