Quarterly report pursuant to Section 13 or 15(d)

Secured Loans Receivable (Loans Receivable and Credit Quality Indicators) (Details)

v3.8.0.1
Secured Loans Receivable (Loans Receivable and Credit Quality Indicators) (Details) - USD ($)
$ in Thousands
Dec. 31, 2017
Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loan $ 96,971 $ 91,238
Secured loan, percentage 100.00% 100.00%
Secured loans (current) $ 96,971 $ 91,238
Bullion and Numismatic    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loans (current) $ 96,971 $ 91,238
Secured loans (current), percentage 100.00% 100.00%
Bullion and Numismatic | Loan-to-value of 75% or more    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loans (current) $ 52,233 $ 60,432
Secured loans (current), percentage 53.90% 66.20%
Bullion and Numismatic | Loan-to-value of less than 75%    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loans (current) $ 44,738 $ 30,806
Secured loans (current), percentage 46.10% 33.80%
Bullion    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loan $ 64,970 $ 61,767
Secured loan, percentage 67.00% 67.70%
Numismatic and semi-numismatic    
Accounts, Notes, Loans and Financing Receivable [Line Items]    
Secured loan $ 32,001 $ 29,471
Secured loan, percentage 33.00% 32.30%