Long-Term Indebtedness (Schedule) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Unamortized deferred financing fees	$ (1,291)	$ (1,774)
Long-term debt, net	738,249	630,789
Less current portion	17,831	17,883
Long-term debt	720,418	612,906
Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	285,000	300,000
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	394,888	266,214
Shelf-Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	50,000	50,000
Other Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 9,652	$ 16,349

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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