Long-term Debt - Debt Table (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Deferred Finance Costs, Net	$ (6,400)	$ (4,160)
Long-term debt, net	393,600	346,290
Credit Agreement [Member]
Debt Instrument [Line Items]
Debt	0	50,450
4.875% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt	0	300,000
4.125% Senior Unsecured Notes Due 2029
Debt Instrument [Line Items]
Debt	$ 400,000	$ 0

Amount of short-term and long-term debt and lease obligation.

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

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Amount of long-term debt and lease obligation, classified as noncurrent.

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