Assets and Liabilities, at Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Parenthetical) (Details)

v3.21.2

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, 2021	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Commemorative coin inventory, held at lower of cost or net realizable value	$ 709	$ 406