Note 19 - Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information [Text Block]

19. QUARTERLY FINANCIAL DATA (UNAUDITED)

	Three Months Ended
	March 31, 2015		June 30, 2015		September 30, 2015			December 31, 2015
	(in thousands, except per share amounts)
Revenue	$	73,538	$	81,416	$	91,194		$	86,918
Cost of revenue		33,855		37,287		41,754			40,001
Gross profit		39,683		44,129		49,440			46,917
Operating expenses:
Research and development		16,038		15,743		17,272			16,734
Selling, general and administrative		17,518		17,964		18,722			18,107
Litigation expense		270		311		136			283
Total operating expenses		33,826		34,018		36,130			35,124
Income from operations		5,857		10,111		13,310			11,793
Interest and other income (expense), net		642		235		(6	)		550
Income before income taxes		6,499		10,346		13,304			12,343
Income tax provision		536		2,447		2,103			2,233
Net income	$	5,963	$	7,899	$	11,201		$	10,110
Net income per share:
Basic	$	0.15	$	0.20	$	0.28		$	0.26
Diluted	$	0.15	$	0.19	$	0.28		$	0.24
Weighted-average shares outstanding:
Basic		39,105		39,570		39,592			39,615
Diluted		40,596		40,745		40,689			41,445
Cash dividends declared per common share	$	0.20	$	0.20	$	0.20		$	0.20

	Three Months Ended
	March 31, 2014			June 30, 2014		September 30, 2014			December 31, 2014
	(in thousands, except per share amounts)
Revenue	$	60,061		$	68,436	$	78,335		$	75,703
Cost of revenue		27,964			31,337		35,872			34,744
Gross profit		32,097			37,099		42,463			40,959
Operating expenses:
Research and development		15,603			13,368		14,679			14,941
Selling, general and administrative		16,109			16,853		17,006			16,787
Litigation expense (benefit), net		(8,700	)		274		332			66
Total operating expenses		23,012			30,495		32,017			31,794
Income from operations		9,085			6,604		10,446			9,165
Interest and other income, net		190			295		202			407
Income before income taxes		9,275			6,899		10,648			9,572
Income tax provision (benefit)		257			502		(573	)		712
Net income	$	9,018		$	6,397	$	11,221		$	8,860
Net income per share:
Basic	$	0.23		$	0.17	$	0.29		$	0.23
Diluted	$	0.23		$	0.16	$	0.28		$	0.22
Weighted-average shares outstanding:
Basic		38,470			38,684		38,785			38,807
Diluted		39,517			39,608		39,727			40,321
Cash dividends declared per common share	$	-		$	0.15	$	0.15		$	0.15