Long-term Debt - Debt Table (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt	$ 690,190	$ 346,290
Deferred Finance Costs, Net	(9,810)	(4,160)
Current maturities, debt	300,000	0
Long-term debt, net	390,190	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	300,000	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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-Name Accounting Standards Codification
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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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