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

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The number of shares converted from each common unit.

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The number of shares issued through conversion upon the reorganization of the reporting entity.

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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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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of common units issued of limited liability company (LLC).

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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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Number of preferred units issued of limited liability company (LLC).

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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

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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of new stock issued during the period.

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Note 7 - Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions			6 Months Ended	12 Months Ended
	Feb. 08, 2017	Aug. 31, 2016	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Common Unit, Issued			8,000,000
Limited Liability Company (LLC) Preferred Unit, Issued			4,538,836
Common Stock, Shares Authorized				260,000,000	260,000,000
Common Stock, Par or Stated Value Per Share				$ 0.01	$ 0.01
Preferred Stock, Shares Authorized				50,000,000	50,000,000
Preferred Stock, Par or Stated Value Per Share				$ 0.01	$ 0.01
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				5,900,000
Allocated Share-based Compensation Expense, Total			$ 0.3	$ 2.6	$ 2.8
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		333,334
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 15
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
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
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total			$ 0.3		2.1
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term				6 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate				51.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate				1.32%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate				0.00%
Restricted Stock [Member]
Allocated Share-based Compensation Expense, Total				$ 2.6	$ 0.7
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total				$ 3.8
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				1 year 146 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value				$ 0.2
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
IPO [Member]
Sale of Stock, Conversion of Each Common Unit	2.81
Stock Issued During Period, Shares, New Issues	6,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01
IPO [Member] \| Conversion of Common Units Into Common Stock [Member]
Stock Issued During Period, Shares, Conversion Upon Reorganization	35,262,576
IPO [Member] \| Common Stock Sold by the Company [Member]
Stock Issued During Period, Shares, New Issues	3,800,000