Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 6,785	$ 7,061	$ 7,631
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	16,451	17,710	18,247
Provision for doubtful accounts	5,552	4,640	5,225
Noncash amortization of debt financing costs	840	1,059	891
Pension plan contributions	(2,995)	(2,958)	(2,965)
Loss on early extinguishment of debt	0	591	0
Shared-based compensation expense	2,607	2,853	2,741
Loss on sale of assets	80	596	1,098
Deferred income taxes	(2,525)	8,157	3,277
Noncash loss on forward exchange contracts	603	151	483
Insurance Settlement	(675)	0	0
Impairment of equipment held for sale	616	0	0
Change in other operating items:
Accounts receivable	25,501	166	(27,875)
Inventories	2,993	6,761	(5,370)
Prepaid expenses	(978)	(3,743)	2,267
Accounts payable	(4,263)	(3,642)	3,065
Accrued liabilities	(1,997)	8,211	1,022
Other operating activities, net	770	7,686	(218)
Net cash provided by operating activities	49,365	55,299	9,519
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(11,429)	(14,685)	(13,704)
Proceeds from disposal/sale of property, plant and equipment	37	108	689
Proceeds from corporate-owned life insurance policies	2,489	0	0
Other investing activities, net	0	71	726
Net cash used in investing activities	(8,903)	(14,506)	(12,289)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from borrowings against life insurance policies	0	0	1,041
Surrender of common stock by employees	(714)	(417)	(527)
Redemption of Notes	0	(15,000)	0
Early payment fee on debt and other debt issuance costs	0	(591)	0
Net cash (used in) provided by financing activities	(714)	(16,008)	514
EFFECT OF CURRENCY EXCHANGE RATE CHANGES ON CASH	(1,782)	(2,682)	(348)
NET INCREASE (DECREASE) IN CASH	37,966	22,103	(2,604)
CASH:
Beginning of period	92,194	70,091	72,695
End of period	130,160	92,194	70,091
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	18,684	19,939	19,831
Cash paid for income taxes, net	2,495	1,545	1,387
Unpaid purchases of property and equipment included in accounts payable	$ 488	$ 905	$ 864