CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash provided by (used for) operating activities:
Net income (loss)	$ (587)	$ 119
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Depreciation and amortization	8,243	7,645
Provision for doubtful accounts	4	23
Provision for inventory write-downs	756	659
Deferred income taxes	913	(496)
Shares issued for employee benefit plan	335	346
Employee and director stock-based compensation	2,204	2,623
Performance-based common stock warrants	471	932
Changes in operating assets and liabilities:
Accounts receivable and contract assets	(266)	(3,689)
Inventories	1,372	(1,564)
Prepaid expenses and other assets	(454)	(905)
Accounts payable and accrued liabilities	(21,160)	(16,182)
Accrued income taxes	(3,774)	(2,064)
Net cash provided by (used for) operating activities	(11,943)	(12,553)
Cash used for investing activities:
Acquisitions of property, plant, and equipment	(9,314)	(6,460)
Acquisitions of intangible assets	(571)	(410)
Net cash used for investing activities	(9,885)	(6,870)
Cash provided by (used for) financing activities:
Borrowings under line of credit	13,000	53,000
Repayments on line of credit	(10,000)	(14,987)
Proceeds from stock options exercised	439	237
Treasury stock purchased	(615)	(11,389)
Contingent consideration payments in connection with business combinations	(3,858)	0
Net cash provided by (used for) financing activities	(1,034)	26,861
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	832	25
Net increase (decrease) in cash, cash equivalents, and restricted cash	(22,030)	7,463
Cash, cash equivalents, and restricted cash at beginning of year	67,339	59,834
Cash, cash equivalents, and restricted cash at end of period	45,309	67,297
Supplemental cash flow information:
Income taxes paid	2,893	2,925
Interest paid	$ 1,164	$ 414