Debt (Details Textual) - USD ($) shares in Thousands, $ in Thousands		1 Months Ended	12 Months Ended
	Feb. 21, 2024	Mar. 31, 2021	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Gain on debt extinguishment			$ 417	$ 3,437	$ 0
Finance Lease Obligations			$ 54,300
Line of Credit
Debt Instrument [Line Items]
Stated interest rate			7.00%
Line of Credit | Rochester Finance Lease
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 60,000
Revolving Credit Facility | Minimum | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.00%
Revolving Credit Facility | Minimum | London Interbank Offered Rate (LIBOR) 1
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			2.00%
Revolving Credit Facility | Maximum | Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			1.75%
Revolving Credit Facility | Maximum | London Interbank Offered Rate (LIBOR) 1
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate			2.75%
Senior Notes due 2029
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 375,000
Proceeds from debt		$ 367,500
Extinguishment of debt			$ 5,900
Stated interest rate			5.125%
Converted shares (in shares)			1,800
Gain on debt extinguishment			$ 400
Rochester Finance Lease | Line of Credit
Debt Instrument [Line Items]
Stated interest rate			5.20%
Revolving Credit Facility
Debt Instrument [Line Items]
Additional increases in RCF	$ 100,000
Non-capitalized underground mine development costs	15,000
Letters of credit outstanding, amount			$ 29,300
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Stated interest rate			6.70%
Long-term debt			$ 195,000
Amount available subject to debt covenants			$ 175,700
Revolving Credit Facility | Credit Agreement | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000