| 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, aggregated by each fair value hierarchy level (in thousands):   
       
        |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
        |   |   | September 30, 2024 |   |  
        |   |   | Quoted Price in Active Markets for Identical Instruments(Level 1)
 |   |   | Significant Other Observable Inputs(Level 2)
 |   |   | Significant Unobservable Inputs(Level 3)
 |   |   | Total |   |  
        | Assets: |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Inventories(1) |   | $ | 1,274,196 |   |   | $ | — |   |   | $ | — |   |   | $ | 1,274,196 |   |  
        | Precious metals held under financing arrangements |   |   | 27,354 |   |   |   | — |   |   |   | — |   |   |   | 27,354 |   |  
        | Derivative assets — open sale and purchase commitments, net |   |   | 105,083 |   |   |   | — |   |   |   | — |   |   |   | 105,083 |   |  
        | Derivative assets — futures contracts |   |   | 61 |   |   |   | — |   |   |   | — |   |   |   | 61 |   |  
        | Derivative assets — forward contracts |   |   | 3,577 |   |   |   | — |   |   |   | — |   |   |   | 3,577 |   |  
        | Total assets, valued at fair value |   | $ | 1,410,271 |   |   | $ | — |   |   | $ | — |   |   | $ | 1,410,271 |   |  
        | Liabilities: |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Liabilities on borrowed metals |   | $ | 39,487 |   |   | $ | — |   |   | $ | — |   |   | $ | 39,487 |   |  
        | Product financing arrangements |   |   | 541,744 |   |   |   | — |   |   |   | — |   |   |   | 541,744 |   |  
        | Derivative liabilities — open sale and purchase commitments, net |   |   | 10,663 |   |   |   | — |   |   |   | — |   |   |   | 10,663 |   |  
        | Derivative liabilities — margin accounts |   |   | 8,770 |   |   |   | — |   |   |   | — |   |   |   | 8,770 |   |  
        | Derivative liabilities — futures contracts |   |   | 7,231 |   |   |   | — |   |   |   | — |   |   |   | 7,231 |   |  
        | Derivative liabilities — forward contracts |   |   | 19,381 |   |   |   | — |   |   |   | — |   |   |   | 19,381 |   |  
        | Acquisition-related contingent consideration |   |   | — |   |   |   | — |   |   |   | 2,280 |   |   |   | 2,280 |   |  
        | Total liabilities, valued at fair value |   | $ | 627,276 |   |   | $ | — |   |   | $ | 2,280 |   |   | $ | 629,556 |   |    
(1)
Commemorative coin inventory totaling $3.1 million was held at lower of cost or net realizable value, and thus is excluded from the inventories balance shown in this table.
   
       
        |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
        |   |   | June 30, 2024 |   |  
        |   |   | Quoted Price in Active Markets for Identical Instruments(Level 1)
 |   |   | Significant Other Observable Inputs(Level 2)
 |   |   | Significant Unobservable Inputs(Level 3)
 |   |   | Total |   |  
        | Assets: |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Inventories (1) |   | $ | 1,093,908 |   |   | $ | — |   |   | $ | — |   |   | $ | 1,093,908 |   |  
        | Precious metals held under financing arrangements |   |   | 22,066 |   |   |   | — |   |   |   | — |   |   |   | 22,066 |   |  
        | Derivative assets — open sale and purchase commitments, net |   |   | 98,012 |   |   |   | — |   |   |   | — |   |   |   | 98,012 |   |  
        | Derivative assets — futures contracts |   |   | 1,557 |   |   |   | — |   |   |   | — |   |   |   | 1,557 |   |  
        | Derivative assets — forward contracts |   |   | 15,151 |   |   |   | — |   |   |   | — |   |   |   | 15,151 |   |  
        | Total assets, valued at fair value |   | $ | 1,230,694 |   |   | $ | — |   |   | $ | — |   |   | $ | 1,230,694 |   |  
        | Liabilities: |   |   |   |   |   |   |   |   |   |   |   |   |  
        | Liabilities on borrowed metals |   | $ | 31,993 |   |   | $ | — |   |   | $ | — |   |   | $ | 31,993 |   |  
        | Product financing arrangements |   |   | 517,744 |   |   |   | — |   |   |   | — |   |   |   | 517,744 |   |  
        | Derivative liabilities — open sale and purchase commitments, net |   |   | 7,690 |   |   |   | — |   |   |   | — |   |   |   | 7,690 |   |  
        | Derivative liabilities — margin accounts |   |   | 4,766 |   |   |   | — |   |   |   | — |   |   |   | 4,766 |   |  
        | Derivative liabilities — futures contracts |   |   | 39 |   |   |   | — |   |   |   | — |   |   |   | 39 |   |  
        | Derivative liabilities — forward contracts |   |   | 14,256 |   |   |   | — |   |   |   | — |   |   |   | 14,256 |   |  
        | Acquisition-related contingent consideration |   |   | — |   |   |   | — |   |   |   | 2,430 |   |   |   | 2,430 |   |  
        | Total liabilities, valued at fair value |   | $ | 576,488 |   |   | $ | — |   |   | $ | 2,430 |   |   | $ | 578,918 |   |    
(1)
Commemorative coin inventory totaling $3.2 million was 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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