Fair value of non-vested equity-based payment instruments, excluding stock (or unit) options, vested.

No definition available.

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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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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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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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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

+ References

No definition available.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Number of share options (or share units) exercised during the current period.

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Note 5 - Share-based Compensation (Details Textual) - USD ($)		3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 27, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Allocated Share-based Compensation Expense, Total		$ 374,380	$ 313,873	$ 747,805	$ 643,768
Employee Stock Option [Member]
Allocated Share-based Compensation Expense, Total		149,612	146,538	302,315	316,861
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		21,325,800		21,325,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		15,888,154		15,888,154
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 723,532	$ 21,104	$ 993,773	$ 91,817
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 0	$ 0	$ 0	$ 1.13
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term				5 years 328 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term				5 years 182 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total		$ 848,055		$ 848,055
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				1 year 292 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				142,914
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				35,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member]
Allocated Share-based Compensation Expense, Total		126,901	$ 126,903	$ 252,408	$ 252,411
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		9,428,021		9,428,021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		4,543,060		4,543,060
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		285,250		285,250
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total		256,592		$ 256,592
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				182 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized						1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Exercise Price						$ 1.64
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	999,997
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			0		0
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period				3 years 182 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				0
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member] \| Vesting on Release of Audited Financial Statements for 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage						50.00%
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member] \| Vesting One Year After Release of Audited Financial Statements for 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage						50.00%
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Restricted Stock [Member]
Allocated Share-based Compensation Expense, Total		97,867	$ 40,432	$ 193,082	$ 74,496
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total		1,241,718		$ 1,241,718
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				3 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value		154,440	0	$ 1,125,048	364,936
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 173,678	$ 20,123	$ 480,736	$ 61,157