Quarterly report pursuant to Section 13 or 15(d)

Financing Agreements (Narrative) (Details)

v3.5.0.2
Financing Agreements (Narrative) (Details) - USD ($)
 3 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Jun. 30, 2016
Mar. 31, 2016
Schedule Of Financing Arrangements [Line Items]        
Liability on borrowed metals $ 4,196,000   $ 4,352,000  
Product financing obligation 117,789,000   59,358,000  
Line of Credit | Trading credit facility        
Schedule Of Financing Arrangements [Line Items]        
Interest expense, notes payable $ 1,500,000 $ 1,100,000    
Percentage of total expense recognized 65.00% 92.10%    
Effective rate of interest (percentage) 2.98% 2.83%    
Line of Credit | Trading credit facility | A-Mark | Trading credit facility        
Schedule Of Financing Arrangements [Line Items]        
Line of credit, maximum borrowing capacity       $ 275,000,000
Line of credit, current borrowing capacity       225,000,000
Line of credit, accordion option       $ 50,000,000
Payments of financing costs $ 800,000      
Accumulated amortization of loan cost $ 500,000   $ 600,000  
Variable rate basis one-month LIBOR      
Credit facility, interest rate at period end (percentage) 0.53%   0.47%  
Borrowings due on demand $ 203,000,000   $ 212,000,000  
Credit facility, remaining borrowing capacity 22,000,000   $ 17,800,000  
Credit facility, minimum required tangible net worth $ 35,000,000      
LIBOR | Line of Credit | Revolving Credit Facility        
Schedule Of Financing Arrangements [Line Items]        
Variable rate (percentage) 2.50%      
LIBOR | Line of Credit | Bridge Loan        
Schedule Of Financing Arrangements [Line Items]        
Variable rate (percentage) 4.50%