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Long-Term Debt (Schedule of Long-Term Debt) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Instrument [Line Items] |  |
Total debt | $ 285,386 | $ 443,981
Less current maturities | 15,066 | 18,840
Total long-term debt | 270,320 | 425,141
Term debt |  |
Debt Instrument [Line Items] |  |
Total debt | 280,233 | 298,717
Finance lease liability |  |
Debt Instrument [Line Items] |  |
Total debt | 153 |
Capital lease obligations |  |
Debt Instrument [Line Items] |  |
Total debt |  | 264
Line of Credit | Bank revolving credit facility |  |
Debt Instrument [Line Items] |  |
Total debt | $ 5,000 | $ 145,000

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