The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Note 9 - Stock-Based Compensation (Details) - Stock Options Outstanding and Exercisable - $ / shares	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options outstanding (in Shares)	361,470	759,683	458,573	503,834
Outstanding options, weighted-average exercise price	$ 9.16	$ 11.36	$ 10.54	$ 10.41
Outstanding options, weighted-average remaining contractual life	3 years 47 days
Exercisable options, stock options exercisable (in Shares)	292,760
Exercisable options, weighted-average exercise price	$ 9.60
Range 1 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options, exercise price range, lower limit	5.76
Outstanding options, exercise price range, upper limit	$ 9.21
Stock options outstanding (in Shares)	221,669
Outstanding options, weighted-average exercise price	$ 5.76
Outstanding options, weighted-average remaining contractual life	3 years 102 days
Exercisable options, exercise price range, lower limit	$ 5.76
Exercisable options, exercise price range, upper limit	$ 9.21
Exercisable options, stock options exercisable (in Shares)	164,759
Exercisable options, weighted-average exercise price	$ 5.76
Range 2 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options, exercise price range, lower limit	9.22
Outstanding options, exercise price range, upper limit	$ 15.47
Stock options outstanding (in Shares)	108,611
Outstanding options, weighted-average exercise price	$ 12.40
Outstanding options, weighted-average remaining contractual life	2 years 54 days
Exercisable options, exercise price range, lower limit	$ 9.22
Exercisable options, exercise price range, upper limit	$ 15.47
Exercisable options, stock options exercisable (in Shares)	101,941
Exercisable options, weighted-average exercise price	$ 12.51
Range 3 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options, exercise price range, lower limit	15.48
Outstanding options, exercise price range, upper limit	$ 22.66
Stock options outstanding (in Shares)	18,794
Outstanding options, weighted-average exercise price	$ 19.28
Outstanding options, weighted-average remaining contractual life	7 years 9 months
Exercisable options, exercise price range, lower limit	$ 15.48
Exercisable options, exercise price range, upper limit	$ 22.66
Exercisable options, stock options exercisable (in Shares)	15,164
Exercisable options, weighted-average exercise price	$ 19.60
Range 4 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options, exercise price range, lower limit	22.67
Outstanding options, exercise price range, upper limit	$ 32.36
Stock options outstanding (in Shares)	12,396
Outstanding options, weighted-average exercise price	$ 26.18
Outstanding options, weighted-average remaining contractual life	2 years 69 days
Exercisable options, exercise price range, lower limit	$ 22.67
Exercisable options, exercise price range, upper limit	$ 32.36
Exercisable options, stock options exercisable (in Shares)	10,896
Exercisable options, weighted-average exercise price	$ 26.36