CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash provided by (used for) operating activities:
Net income (loss)	$ (3,397)	$ 23,031
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Depreciation and amortization	23,734	25,264
Provision for doubtful accounts	275	2
Provision for inventory write-downs	11,222	6,450
Gain on sale of Guangzhou factory	0	(36,978)
Deferred income taxes	2,273	(1,370)
Shares issued for employee benefit plan	876	880
Employee and director stock-based compensation	6,718	6,808
Performance-based common stock warrants	1,381	747
Impairment of China factory equipment	0	2,886
Changes in operating assets and liabilities:
Accounts receivable and contract assets	(11,117)	(1,289)
Inventories	(6,819)	(9,535)
Prepaid expenses and other assets	5,507	(4,194)
Accounts payable and accrued liabilities	11,686	(13,142)
Accrued income taxes	(2,418)	(4,134)
Net cash provided by (used for) operating activities	39,921	(4,574)
Cash provided by (used for) investing activities:
Proceeds from sale of Guangzhou factory	0	51,291
Acquisitions of property, plant and equipment	(15,854)	(16,838)
Refund of deposit received toward sale of Guangzhou factory	0	(5,053)
Acquisitions of intangible assets	(1,505)	(1,911)
Net cash provided by (used for) investing activities	(17,359)	27,489
Cash provided by (used for) financing activities:
Borrowings under line of credit	57,500	48,000
Repayments on line of credit	(71,000)	(82,500)
Proceeds from stock options exercised	411	864
Treasury stock purchased	(1,741)	(12,564)
Contingent consideration payments in connection with business combinations	(4,251)	(3,858)
Net cash provided by (used for) financing activities	(19,081)	(50,058)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(1,959)	1,799
Net increase (decrease) in cash, cash equivalents and restricted cash	1,522	(25,344)
Cash, cash equivalents and restricted cash at beginning of year	53,207	67,339
Cash, cash equivalents and restricted cash at end of period	54,729	41,995
Supplemental cash flow information:
Income taxes paid	5,608	5,453
Interest paid	$ 3,479	$ 3,722