Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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The ceiling 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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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Note 6 - Share Option and Equity Incentive Plan (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
2013 Plan [Member] \| Second Anniversary of Grant Date [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			40.00%
2013 Plan [Member] \| Third Anniversary of Grant Date [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			30.00%
2013 Plan [Member] \| Fourth Anniversary of Grant Date [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			30.00%
2013 Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	81,185		108,563
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 14.13		$ 14.25
2013 Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	263,619		670,150
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit	$ 14.12		$ 14.12
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit	14.17		14.61
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 6.20		$ 6.41
Employee Stock Option [Member]
Allocated Share-based Compensation Expense	$ 520,000	$ 483,000	$ 1,100,000	$ 660,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	7,300,000		$ 7,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			2 years 255 days
Restricted Stock and Restricted Stock Units (RSU's) [Member]
Allocated Share-based Compensation Expense	193,000	277,000	$ 483,000	365,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	5,400,000		$ 5,400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			3 years
Allocated Share-based Compensation Expense	$ 713,000	$ 760,000	$ 1,588,000	$ 1,025,000