Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Income from continuing operations	$ 15,282	$ 13,078
Income (loss) from discontinued operations	(308)	78
Net income	14,974	13,156
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	3,964	1,718
Benefit from allowance for doubtful accounts	(876)	(118)
Inventory lower-of-cost-or-market adjustments	133	68
Stock-based compensation expense	1,489	669
Loss on asset dispositions	127	258
Deferred income taxes, net of valuation allowance	5,629	7,322
Excess tax (benefit) deficiency related to stock-based awards	(1,729)	1
Other	5	0
Changes in operating assets and liabilities:
Trade receivables	26,260	13,899
Inventories	1,115	(3,537)
Prepaids and other current assets	(445)	2,679
Income taxes receivable	(8,040)	(121)
Trade payables	(17,530)	(15,281)
Accrued liabilities, including warranty obligations	(2,062)	(2,008)
Net cash provided by operating activities	23,014	18,705
Cash flows from investing activities:
Purchases of available-for-sale securities	(20,305)	(43,240)
Proceeds from maturities of available-for-sale securities	16,938	17,095
Proceeds from sales of available-for-sale securities	71	3,381
Acquisition of business, net of cash acquired	(3,468)	0
Purchases of property, plant and equipment	(706)	(1,252)
Net cash used in investing activities	(7,470)	(24,016)
Cash flows from financing activities:
Payments on long-term debt	(8,000)	0
Payments for stock repurchases	0	(1,996)
Proceeds from exercise of stock options and employee stock plan purchases	431	975
Tax payments related to stock award issuances	(221)	(775)
Excess tax benefit (deficiency) related to stock-based awards	1,729	(1)
Net cash used in financing activities	(6,061)	(1,797)
Effect of exchange rate changes on cash and cash equivalents	(77)	(609)
Increase (decrease) in cash and cash equivalents	9,406	(7,717)
Cash and cash equivalents:
Beginning of period	30,778	45,206
End of period	40,184	37,489
Supplemental disclosure of cash flow information:
Cash paid for interest	(975)	(11)
Cash paid for income taxes, net	(11,305)	(760)
Supplemental disclosure of non-cash investing activities:
Capital expenditures incurred but not yet paid	$ 1,701	$ 1,166