Credit Arrangements (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Credit arrangements
Total debt	$ 258,917	$ 261,570
Unamortized debt issuance costs	(102)	(231)
Total debt, net	258,815	261,339
Less: current portion	(65,464)	(58,189)
Long-term debt, net of current portion	193,351	203,150
Scheduled maturities of long-term debt
2018	65,464
2019	62,014
2020	50,755
2021	33,939
2022	24,144
Thereafter	22,601
Commercial equipment notes
Credit arrangements
Total debt, net	165,532	161,148
Mortgages
Credit arrangements
Total debt, net	11,242	7,564
Senior Notes
Credit arrangements
Total debt, net	$ 82,143	$ 92,858

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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-Name Accounting Standards Codification
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