CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
OPERATING ACTIVITIES:
Net income	$ 6,670	$ 3,839
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	1,746	1,346
(Gain) loss on disposals of property, plant and equipment	(39)
Provision for doubtful accounts	56	51
Issuance of non-employee director shares	150	150
Deferred tax provision	207	(25)
Changes in operating assets and liabilities:
Accounts receivable	(3,744)	(7,353)
Inventories	(8,439)	(3,457)
Prepaid expenses	(2,145)	(1,158)
Other assets	18	22
Accounts payable	3,004	2,191
Accrued liabilities	607	1,317
Net cash flows from operating activities	(1,909)	(3,077)
INVESTING ACTIVITIES:
Purchases of property, plant and equipment	(3,880)	(6,393)
Proceeds from sale of property, plant and equipment	60
Net cash flows from investing activities	(3,820)	(6,393)
FINANCING ACTIVITIES:
Net borrowings (payments) under credit facility		5,000
Payments of cash dividends	(2,049)	(2,043)
Proceeds (payments) from other long-term obligations	499
Net cash flows from financing activities	(1,550)	2,957
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND TEMPORARY INVESTMENTS	440	(103)
NET CHANGE IN CASH AND TEMPORARY INVESTMENTS	(6,839)	(6,616)
CASH AND TEMPORARY INVESTMENTS, beginning of period	21,895	31,115
CASH AND TEMPORARY INVESTMENTS, end of period	15,056	24,499
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash payments for interest	521	501
Cash payments for income taxes, net of refunds	$ 758	$ 209