Note 7 - Activity Under the 2004 Equiy Incentive Plan (Details)	6 Months Ended
	Jun. 30, 2016 $ / shares shares
Balance, shares available for grant (in shares)	1,263,425
Balance, stock options outstanding (in shares)	2,148,797
Balance, weighted-average exercise price (in dollars per share) | $ / shares	$ 9.31
Options granted, shares available for grant (in shares)	(93,000)
Options granted, stock options outstanding (in shares)	93,000
Options granted, weighted-average exercise price (in dollars per share) | $ / shares	$ 11.54
Stock awards granted(1) (2) (in shares)	(925,675)	[1],[2]
Options exercised, stock options outstanding (in shares)	(292,934)
Options exercised, weighted-average exercise price (in dollars per share) | $ / shares	$ 8.70
Options canceled, shares available for grant (in shares)	107,620
Options canceled, stock options outstanding (in shares)	(107,620)
Options canceled, weighted-average exercise price (in dollars per share) | $ / shares	$ 13.37
Stock awards canceled(1) (in shares)	206,541	[2]
Balance, shares available for grant (in shares)	558,911
Balance, stock options outstanding (in shares)	1,841,243
Balance, weighted-average exercise price (in dollars per share) | $ / shares	$ 9.28

[1] Included in 'Stock awards granted' of 925,675, was 416,474 fungible shares relating to 196,450 of PSUs granted. These PSUs will result in a higher or lower number of shares of common stock that may be paid out on March 15, 2017, based on the achievement of three performance goals at targets that were pre-determined by the Board and disclosed in a Form 8-K on February 8, 2016.

[2] The Company has a "fungible share" provision in its 2004 Equity Incentive Plan whereby for each full-value award (RSU/PSU) issued or canceled under the Plan, results in a requirement to subtract / add back 2.12 shares from / to the Shares Available for Grant.