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Interest Expense (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	4.20%
Repayments of Long-term Debt	$ 70,000	$ 150,000
Accretion Expense	527	1,271
Amortization of Debt Issuance Costs	$ 1,244	4,031
2018 Term Loan Facility
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	3.50%		3.50%
Repayments of Long-term Debt	$ 70,000	150,000
Accretion Expense	300	900
Amortization of Debt Issuance Costs	$ 500	1,500
Payments of Debt Restructuring Costs		$ 1,600
2020 Senior Secured Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.625%

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Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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