CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash provided by (used for) operating activities:
Net income	$ 22,072	$ 4,803
Adjustments to reconcile net income to net cash provided by (used for) operating activities:
Depreciation and amortization	16,913	15,954
Provision for doubtful accounts	2	81
Provision for inventory write-downs	5,078	1,419
Gain on sale of Guangzhou factory	(36,978)	0
Deferred income taxes	(557)	(1,035)
Shares issued for employee benefit plan	590	591
Employee and director stock-based compensation	4,669	5,555
Performance-based common stock warrants	343	1,263
Impairment of China factory equipment	2,763	0
Changes in operating assets and liabilities:
Accounts receivable and contract assets	6,164	(20,427)
Inventories	(16,061)	(11,249)
Prepaid expenses and other assets	(2,765)	(121)
Accounts payable and accrued liabilities	(7,329)	(15)
Accrued income taxes	1,219	(1,691)
Net cash provided by (used for) operating activities	(3,877)	(4,872)
Cash provided by (used for) investing activities:
Proceeds from sale of Guangzhou factory	51,291	0
Acquisitions of property, plant, and equipment	(13,416)	(17,519)
Refund of deposit received toward sale of Guangzhou factory	(5,053)	0
Acquisitions of intangible assets	(1,248)	(765)
Acquisition of net assets of Residential Control Systems, Inc.	0	(8,854)
Net cash provided by (used for) investing activities	31,574	(27,138)
Cash provided by (used for) financing activities:
Borrowings under line of credit	23,000	85,000
Repayments on line of credit	(50,000)	(42,987)
Proceeds from stock options exercised	704	842
Treasury stock purchased	(7,114)	(14,885)
Contingent consideration payments in connection with business combinations	(3,858)	0
Net cash provided by (used for) financing activities	(37,268)	27,970
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	1,665	(1,383)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(7,906)	(5,423)
Cash, cash equivalents, and restricted cash at beginning of year	67,339	59,834
Cash, cash equivalents, and restricted cash at end of period	59,433	54,411
Supplemental cash flow information:
Income taxes paid	4,191	4,142
Interest paid	$ 2,525	$ 981