Inventories - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2025	Jun. 30, 2025
Inventory [Line Items]
Inventory held for sale	$ 1,031,156	$ 794,812
Precious metals inventory subject to repurchase arrangements	94,700	116,500
Consignment arrangements with customers	4,200	6,000
Collectible coin inventory, held at lower of cost or net realizable value	76,096	68,193
Product financing arrangement, restricted	504,600	484,700
Unrealized gains (losses) included in inventory balance	187,400	94,800
Premium on metals position	20,816	35,295
Inventories
Inventory [Line Items]
Borrowed precious metals from suppliers	85,600	46,100
Inventory held for Sale
Inventory [Line Items]
Inventory held for sale	$ 770,526	$ 558,024