Credit Arrangements (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Credit arrangements
Total debt	$ 352,088	$ 369,158
Unamortized debt issuance costs	(787)	(1,001)
Total debt, net	351,301	368,157
Less: current portion	(55,659)	(62,488)
Long-term debt, net of current portion	295,642	305,669
Scheduled maturities of long-term debt
2020	55,659
2021	43,728
2022	39,032
2023	173,575
2024	5,990
Thereafter	34,104
Term Loan
Credit arrangements
Total debt, net	203,500	214,500
Commercial equipment notes
Credit arrangements
Total debt	105,114	127,458
Mortgages
Credit arrangements
Total debt, net	$ 43,474	$ 27,200

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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