| Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis | The following tables present information about the Company's assets and liabilities measured at fair value on a recurring basis as of December 31, 2022 and June 30, 2022, aggregated by each fair value hierarchy level:    
       
        |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
        | in thousands |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | December 31, 2022 |   |  
        |   |   | Quoted |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | Price in |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | Active Markets |   |   |   | Significant Other |   |   |   | Significant |   |   |   |   |   |  
        |   |   | for Identical |   |   |   | Observable |   |   |   | Unobservable |   |   |   |   |   |  
        |   |   | Instruments |   |   |   | Inputs |   |   |   | Inputs |   |   |   |   |   |  
        |   |   | (Level 1) |   |   |   | (Level 2) |   |   |   | (Level 3) |   |   |   | Total |   |  
        | Assets: |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Inventories(1) |   | $ | 921,341 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 921,341 |   |  
        | Precious metals held under financing arrangements |   |   | 57,287 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 57,287 |   |  
        | Derivative assets — open sale and purchase commitments, net |   |   | 41,673 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 41,673 |   |  
        | Derivative assets — forward contracts |   |   | 115 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 115 |   |  
        | Option to purchase interest in a long-term investment |   |   | — |   |   |   |   | — |   |   |   |   | 5,300 |   |   |   |   | 5,300 |   |  
        | Total assets, valued at fair value |   | $ | 1,020,416 |   |   |   | $ | — |   |   |   | $ | 5,300 |   |   |   | $ | 1,025,716 |   |  
        | Liabilities: |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Liabilities on borrowed metals |   | $ | 31,109 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 31,109 |   |  
        | Product financing arrangements |   |   | 347,260 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 347,260 |   |  
        | Derivative liabilities — open sale and purchase commitments, net |   |   | 13,473 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 13,473 |   |  
        | Derivative liabilities — margin accounts |   |   | 5,612 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 5,612 |   |  
        | Derivative liabilities — futures contracts |   |   | 9,184 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 9,184 |   |  
        | Derivative liabilities — forward contracts |   |   | 74,665 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 74,665 |   |  
        | Total liabilities, valued at fair value |   | $ | 481,303 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 481,303 |   |    
(1)
Commemorative coin inventory totaling $1.2 million is held at lower of cost or realizable value, and thus is excluded from the inventories balance shown in this table.
   
       
        |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
        | in thousands |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | June 30, 2022 |   |  
        |   |   | Quoted |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | Price in |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        |   |   | Active Markets |   |   |   | Significant Other |   |   |   | Significant |   |   |   |   |   |  
        |   |   | for Identical |   |   |   | Observable |   |   |   | Unobservable |   |   |   |   |   |  
        |   |   | Instruments |   |   |   | Inputs |   |   |   | Inputs |   |   |   |   |   |  
        |   |   | (Level 1) |   |   |   | (Level 2) |   |   |   | (Level 3) |   |   |   | Total |   |  
        | Assets: |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Inventories(1) |   | $ | 739,584 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 739,584 |   |  
        | Precious metals held under financing arrangements |   |   | 79,766 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 79,766 |   |  
        | Derivative assets — open sale and purchase commitments, net |   |   | 27,423 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 27,423 |   |  
        | Derivative assets — futures contracts |   |   | 20,245 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 20,245 |   |  
        | Derivative assets — forward contracts |   |   | 44,075 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 44,075 |   |  
        | Option to purchase interest in a long-term investment |   |   | — |   |   |   |   | — |   |   |   |   | 5,300 |   |   |   |   | 5,300 |   |  
        | Total assets, valued at fair value |   | $ | 911,093 |   |   |   | $ | — |   |   |   | $ | 5,300 |   |   |   | $ | 916,393 |   |  
        | Liabilities: |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Liabilities on borrowed metals |   | $ | 59,417 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 59,417 |   |  
        | Product financing arrangements |   |   | 282,671 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 282,671 |   |  
        | Derivative liabilities — open sale and purchase commitments, net |   |   | 70,564 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 70,564 |   |  
        | Derivative liabilities — margin accounts |   |   | 4,686 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 4,686 |   |  
        | Derivative liabilities — forward contracts |   |   | 530 |   |   |   |   | — |   |   |   |   | — |   |   |   |   | 530 |   |  
        | Total liabilities, valued at fair value |   | $ | 417,868 |   |   |   | $ | — |   |   |   | $ | — |   |   |   | $ | 417,868 |   |    
(1)
Commemorative coin inventory totaling $1.4 million is held at lower of cost or net realizable value, and thus is excluded from the inventories balance shown in this table.
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