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

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Percent of shares that may be issued in accordance with the plan as a proportion of outstanding awards.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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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 award under share-based payment arrangement.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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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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Note 6 - Share-based Compensation (Details Textual) - USD ($)			3 Months Ended		6 Months Ended		12 Months Ended
	Apr. 01, 2019	Feb. 27, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017
Share-based Payment Arrangement, Expense			$ 646,000	$ 374,000	$ 1,252,000	$ 748,000
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense			95,000	149,000	240,000	303,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value			27,200,000		27,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value			24,100,000		24,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			2,000,000	724,000	$ 3,500,000	$ 1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term					5 years 73 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term					5 years 36 days
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			279,000		$ 279,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition					1 year 146 days
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross
Performance Shares [Member] \| Management Performance Bonus Plan 2017 [Member]
Share-based Payment Arrangement, Expense			0	127,000	$ 0	$ 252,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value			14,800,000		14,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value			14,800,000		14,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 0	$ 285,000	$ 0	$ 285,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			0	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term					2 years 182 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term					2 years 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
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 Payment Arrangement, 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 Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		50.00%
Restricted Stock [Member]
Share-based Payment Arrangement, Expense			$ 268,000	$ 98,000	$ 522,000	$ 193,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			3,600,000		$ 3,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition					3 years 146 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Fair Value			548,000	154,000	$ 3,200,000	1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			369,000	$ 174,000	$ 1,200,000	$ 481,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					177,718
Performance-based Restricted Stock [Member]
Share-based Payment Arrangement, Expense			283,000		$ 490,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total			$ 1,700,000		$ 1,700,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition					1 year 182 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			94,247		94,247
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	29,604				123,851
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding			$ 2,200,000		$ 2,200,000
Performance-based Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Awards					0.00%
Performance-based Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			188,494		188,494
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Awards					200.00%