v3.26.1
Contingencies - Schedule of Contingencies Reserve Balance (Details) - New Idria Mercury Mine [Member] - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Loss Contingencies [Line Items]        
Beginning reserve balance $ 12,080 $ 11,719 $ 12,504 $ 12,425
Changes in estimated environmental liability 500 0 1,500 0
Payments made (1,367) (478) (2,791) (1,184)
Ending reserve balance [1] 11,213 11,241 11,213 11,241
Beginning receivable balance 8,239 7,487 8,332 8,404
Changes in estimated insurance recovery 500 0 1,100 0
Insurance recovery reimbursements (835) (437) (1,528) (1,354)
Ending receivable balance [2] $ 7,904 $ 7,050 $ 7,904 $ 7,050
[1]

(1) As of June 30, 2026, Buckhorn has a total ending reserve balance of $11.2 million related to the New Idria Mine, of which $7.9 million is classified in Other current liabilities, $2.9 million in Other liabilities (long-term) and $0.4 million in Accounts payable.
[2]

(2) As of June 30, 2026, Buckhorn has a total receivable balance related to the probable insurance recovery of $7.9 million, of which $4.5 million is classified in Other accounts receivable and $3.4 million is classified in Other assets (long-term).