| Secured Loans Receivable - Schedule of Financing Receivable Credit Quality Indicators (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Jun. 30, 2024 | 
|---|---|---|
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Secured loans (current) | $ 101,887 | $ 113,067 | 
| Bullion and Numismatic and Semi-numismatic and Graded Sports Memorabilia | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Secured loans (current) | $ 101,887 | $ 113,067 | 
| Secured loans (current), percentage | 100.00% | 100.00% | 
| Loan-to-value of 75% or More | Bullion and Numismatic and Semi-numismatic and Graded Sports Memorabilia | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Secured loans (current) | $ 5,730 | $ 11,870 | 
| Secured loans (current), percentage | 5.60% | 10.50% | 
| Loan-to-value of Less than 75% | Bullion and Numismatic and Semi-numismatic and Graded Sports Memorabilia | ||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
| Secured loans (current) | $ 96,157 | $ 101,197 | 
| Secured loans (current), percentage | 94.40% | 89.50% | 
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- Definition Notes, loans and financing receivable, percentage. No definition available. 
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- Definition 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition Amortized cost, after allowance for credit loss, of financing receivable classified as current. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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