CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 8,843	$ 6,343
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	4,315	4,032
Amortization of intangibles	1,792	1,786
Loss on disposal of property and equipment	78	0
Stock-based compensation expense	4,416	4,391
Amortization of premium on marketable securities	260	286
Deferred income taxes	(86)	77
Increase (reduction) in accounts receivable allowances	89	(5)
Tax shortfall associated with employee stock plans	0	189
Change in operating assets and liabilities:
Accounts receivable	(3,565)	(550)
Inventories	6,269	424
Prepaid expenses and other assets	(868)	(227)
Accounts payable	(1,840)	349
Taxes payable and accrued liabilities	(1,413)	(1,076)
Deferred income on sales to distributors	2,001	2,031
Net cash provided by operating activities	20,291	17,672
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(2,095)	(3,322)
Payment for acquisition, net of cash acquired	0	(15,365)
Purchases of marketable securities	(45,227)	0
Proceeds from sales and maturities of marketable securities	38,531	26,785
Net cash (used in) provided by investing activities	(8,791)	8,098
CASH FLOWS FROM FINANCING ACTIVITIES:
Issuance of common stock under employee stock plans	2,957	3,519
Repurchase of common stock	(6,085)	(841)
Payments of dividends to stockholders	(3,729)	(3,519)
Net cash used in financing activities	(6,857)	(841)
NET INCREASE IN CASH AND CASH EQUIVALENTS	4,643	24,929
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	90,092	60,708
CASH AND CASH EQUIVALENTS AT END OF PERIOD	94,735	85,637
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Unpaid property and equipment	1,513	1,295
Unpaid CamSemi purchase consideration	0	184
Loan applied to CamSemi purchase price	0	6,600
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for income taxes, net	$ 613	$ 657