Debt:Summary Table (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Deferred financing costs	$ (5,581)	$ (6,208)
Long-term debt	444,419	443,792
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	0	0
ABL Term Loan Due 2025
Debt Instrument [Line Items]
Long-term Debt, Gross	50,000	50,000
Long-term debt	50,000
4.875% Senior Notes Due 2030 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 400,000	$ 400,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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