Note 8 - Debt, Credit Facility and Leases (Details Textual) $ in Thousands, $ in Millions					12 Months Ended
	Feb. 16, 2026	Jul. 21, 2022 USD ($)	Jul. 09, 2020 CAD ($)	Mar. 19, 2020 USD ($)	Feb. 15, 2026	Feb. 15, 2025	Feb. 15, 2024	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jul. 09, 2020 USD ($) Contract	Jul. 09, 2020 CAD ($) Contract	Feb. 19, 2020 USD ($)	Jul. 31, 2018 USD ($)
Proceeds from Issuance of Long-term Debt, Total								$ 25,000	$ 0	$ 716,327
Line of Credit Facility, Maximum Borrowing Capacity								150,000
Net finance lease obligation								20,859	13,400
Finance leases								9,483	5,612
Finance Lease, Liability, Noncurrent								11,400	$ 7,800
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total								$ 23,100
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]								Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Finance Lease, Right-of-Use Asset, Amortization								$ 7,100	$ 8,900	7,400
Finance Lease, Interest Expense								900	600	600
Finance Lease, Liability, Payment, Due, Total								22,220
Finance Lease, Liability, Undiscounted Excess Amount								$ 1,361
Finance Lease, Weighted Average Remaining Lease Term (Year)								1 year 10 months 24 days
Finance Lease, Weighted Average Discount Rate, Percent								6.50%
Operating Lease, Weighted Average Discount Rate, Percent								6.00%
Operating Lease, Liability								$ 11,068	$ 12,400
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]								Operating Lease, Liability	Operating Lease, Liability
Operating Lease								$ 2,500	$ 2,500
Operating Lease, Liability, Noncurrent								8,600	10,000
Operating Lease, Right-of-Use Asset								11,064	12,435
Operating Lease, Expense								3,100	3,900	7,200
Finance Lease, Liability								$ 20,859	$ 13,400
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]								Finance Lease, Liability	Finance Lease, Liability
Lessee, Operating Lease, Liability, to be Paid, Total								$ 14,579
Operating Lease, Weighted Average Remaining Lease Term (Year)								8 years 10 months 24 days
Properties, Plants, Equipment and Mineral Interests [Member]
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total									$ 18,300
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity														$ 250,000
Long-term Line of Credit								$ 0
Letter of Credit [Member]
Letter of Credit Outstanding, Fronting Fee														0.20%
Letter of Credit [Member] | Minimum [Member]
Letter of Credit, Participation Fee, Percent														2.25%
Letter of Credit [Member] | Maximum [Member]
Letter of Credit, Participation Fee, Percent														4.00%
New Credit Agreement [Member]
Line of Credit Facility, Maximum Borrowing Capacity								142,200
Long-term Line of Credit								7,800
New Credit Agreement [Member] | Revolving Credit Facility [Member]
Interest Expense, Debt, Total								$ 300
Line of Credit Facility, Maximum Borrowing Capacity		$ 150,000
Line of Credit Facility, Maximum Borrowing Capacity, Option		$ 75,000
New Credit Agreement [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Line of Credit Facility, Commitment Fee Percentage		0.45%
New Credit Agreement [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Line of Credit Facility, Commitment Fee Percentage		0.7875%
New Credit Agreement [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate								2.00%
New Credit Agreement [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate								3.50%
New Credit Agreement [Member] | Base Rate [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate								1.00%
Debt Instrument, Basis Spread on Variable Rate, Applicable Margin		1.00%
New Credit Agreement [Member] | Base Rate [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate								2.50%
New Credit Agreement [Member] | Fed Funds Effective Rate Overnight Index Swap Rate [Member] | Revolving Credit Facility [Member]
Debt Instrument, Basis Spread on Variable Rate								50.00%
New Credit Agreement [Member] | Leverage Ratio Applicable Margin [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument, Participation Fee, Percent		2.00%
New Credit Agreement [Member] | Leverage Ratio Applicable Margin [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument, Participation Fee, Percent		3.50%
Prior Credit Agreement [Member] | Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity								$ 250,000
Senior Notes [Member]
Long-term debt balance								$ 506,366	$ 508,095
Senior Notes [Member] | The 2028 Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage								7.25%					7.25%
Debt Instrument, Face Amount													$ 475,000
Underwriting Discount on Senior Notes													1.16%
Debt Instrument, Unamortized Discount, Total													$ 5,500
Debt Instrument, Redemption Price, Percentage, Net of Cash Proceeds of Equity Offerings									35.00%
Debt Instrument, Redemption Price, Percentage, Including Accrued and Unpaid Interest									101.00%
Long-term debt balance								$ 470,360	$ 469,448
Senior Notes [Member] | The 2028 Senior Notes [Member] | Forecast [Member]
Debt Instrument, Redemption Price, Percentage	100.00%				101.813%	103.625%	105.438%
Senior Notes [Member] | The 2021 Senior Notes [Member]
Proceeds from Issuance of Long-term Debt, Total				$ 469,500
Previously Outstanding				6.875%
Interest Expense, Debt, Total								35,400	35,400	40,200
Debt Instrument, Unamortized Discount (Premium), Net, Total									1,700
Senior Notes [Member] | IQ Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage											6.515%	6.515%
Debt Instrument, Face Amount											$ 36,800	$ 50.0
Interest Expense, Debt, Total								2,300	2,300	$ 900
Debt Instrument, Unamortized Premium, Percentage of Principal											103.65%	103.65%
Debt Instrument, Unamortized Premium, Total												$ 1.8
Debt Instrument, Effective Annual Yield											5.74%	5.74%
Long-term debt balance								$ 36,006	$ 38,647			$ 48.2
Debt Instrument, Number of Issuance Installments | Contract											4	4
Proceeds from Issuance of Debt			$ 12.5
Payments of Debt Issuance Costs			$ 0.6
Debt Instrument, Covenant, Investment Over Next Four Years												$ 100.0