Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income(loss)	$ 7,407	$ (1,299)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	15,568	17,348
Amortization of debt issuance costs	1,221	911
Total derivative mark-to-market gains, net of cash settlements	(88)
Joint venture net income in excess of cash received	(1,693)	(1,400)
Compensation expense from issuance of restricted stock and incentive stock options	1,152	1,001
Deferred income tax benefit		1,029
Changes in operating assets and liabilities:
Accounts receivable	(19,332)	(20,318)
Inventories	(1,025)	(283)
Accounts payable	1,394	1,191
Other	605	5,341
Net cash provided by operating activities	5,209	3,521
Cash flows from investing activities:
Acquisition of property, plant and equipment	(8,565)	(8,008)
Proceeds from disposals of property, plant and equipment	27	17
Net cash used by investing activities	(8,538)	(7,991)
Cash flows from financing activities:
Dividends Paid	(1,910)	(1,879)
Proceeds from long-term debt	14,000	11,000
Repayment of long-term debt	(1,437)	(1,437)
Repayment of short-term debt, net	(2,045)	(969)
Proceeds from issuance of stock and exercise of stock options	912
Shares withheld to satisfy income tax withholding	(327)	(89)
Principal payments on capital lease	(901)	(1,342)
Net cash provided by financing activities	8,292	5,284
Effect of exchange rate changes on cash flows	215	(822)
Net change in cash and cash equivalents	5,178	(8)
Cash and cash equivalents at beginning of period	14,405	15,087
Cash and cash equivalents at end of period	$ 19,583	$ 15,079