CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash provided by (used for) operating activities:
Net income (loss)	$ (6,066)	$ 22,072
Adjustments to reconcile net income (loss) to net cash provided by (used for) operating activities:
Depreciation and amortization	15,871	16,913
Provision for doubtful accounts	5	2
Provision for inventory write-downs	7,016	5,078
Gain on sale of Guangzhou factory	0	(36,978)
Deferred income taxes	3,203	(557)
Shares issued for employee benefit plan	620	590
Employee and director stock-based compensation	4,191	4,669
Performance-based common stock warrants	670	343
Impairment of China factory equipment	0	2,763
Changes in operating assets and liabilities:
Accounts receivable and contract assets	(8,108)	6,164
Inventories	(11,403)	(16,061)
Prepaid expenses and other assets	2,578	(2,765)
Accounts payable and accrued liabilities	16,822	(7,329)
Accrued income taxes	(5,166)	1,219
Net cash provided by (used for) operating activities	20,233	(3,877)
Cash provided by (used for) investing activities:
Proceeds from sale of Guangzhou factory	0	51,291
Acquisitions of property, plant and equipment	(10,093)	(13,416)
Refund of deposit received toward sale of Guangzhou factory	0	(5,053)
Acquisitions of intangible assets	(1,260)	(1,248)
Net cash provided by (used for) investing activities	(11,353)	31,574
Cash provided by (used for) financing activities:
Borrowings under line of credit	40,000	23,000
Repayments on line of credit	(46,500)	(50,000)
Proceeds from stock options exercised	0	704
Treasury stock purchased	(1,404)	(7,114)
Contingent consideration payments in connection with business combinations	(4,251)	(3,858)
Net cash provided by (used for) financing activities	(12,155)	(37,268)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(367)	1,665
Net increase (decrease) in cash, cash equivalents and restricted cash	(3,642)	(7,906)
Cash, cash equivalents and restricted cash at beginning of year	53,207	67,339
Cash, cash equivalents and restricted cash at end of period	49,565	59,433
Supplemental cash flow information:
Income taxes paid	3,973	4,191
Interest paid	$ 1,156	$ 2,525