The number of common stock options converted from common unit options during a noncash transaction during the period.

No definition available.

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- Definition

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

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Publisher FASB
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- Definition

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

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-Publisher FASB
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- Definition

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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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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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- Definition

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

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- Definition

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 5 - Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		12 Months Ended
	Aug. 31, 2016	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2018
Common Stock, Shares, Outstanding, Ending Balance		40,832,890			40,082,467
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		5,200,000
Share-based Payment Arrangement, Expense		$ 0.9	$ 0.6	$ 2.1
Noncash Transaction, Conversion of Common Unit Options, Number of Common Stock Options	937,424
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance	$ 5.34
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Restricted Stock [Member]
Share-based Payment Arrangement, Expense		0.9	$ 0.6
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 7.1
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		1 year 219 days
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		1 year
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years