Annual report pursuant to Section 13 and 15(d)

Description of Business - Joint Venture and Acquisition (Details)

v3.7.0.1
Description of Business - Joint Venture and Acquisition (Details) - USD ($)
1 Months Ended
Aug. 31, 2016
Aug. 31, 2017
Jun. 30, 2017
Jun. 30, 2016
SilverTowne        
Business Acquisition [Line Items]        
Payments to acquire interest in JV $ 3,453,750      
A-MARK PRECIOUS METALS, INC        
Business Acquisition [Line Items]        
Payments to acquire interest in JV 3,721,250      
Scenario, Forecast | SilverTowne        
Business Acquisition [Line Items]        
Ownership percentage (percentage)   45.00%    
Scenario, Forecast | A-MARK PRECIOUS METALS, INC        
Business Acquisition [Line Items]        
Payments to acquire interest in JV   $ 500,000    
Ownership percentage (percentage)   55.00%    
SilverTowne Mint        
Business Acquisition [Line Items]        
Payments to acquire assets 3,171,250      
Working capital acquired 300,000      
Purchase price 3,671,250      
Payment towards the acquisition $ 3,171,250      
Earn-out Period (years) 3 years      
Contingent liability $ 1,000,000.0      
Fair value of the assets acquired 7,675,000      
Contingent earn-out consideration $ 1,523,000      
SilverTowne Mint | AM&ST Associates, LLC        
Business Acquisition [Line Items]        
Asset contributed (percentage) 48.47%      
Remaining assets purchased (percentage) 51.53%      
Land and Building | SilverTowne Mint        
Business Acquisition [Line Items]        
Payments to acquire assets $ 250,000      
Asahi Refining USA, Inc        
Business Acquisition [Line Items]        
Option to purchase investment     10.00%  
Commercial Paper | SilverTowne Mint        
Business Acquisition [Line Items]        
Liabilities incurred for the acquisition $ 500,000      
Debt instrument, term (years) 1 year      
Contingent Consideration Liability        
Business Acquisition [Line Items]        
Contingent consideration, adjusted balance     $ 1,325,000 $ 0