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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

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

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- Definition

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

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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-Paragraph 2
-Subparagraph (f)(2)(i)
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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Fair value at acquisition-date of the share-based awards attributed to pre-acquisition service.

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EQUITY BASED COMPENSATION - Rockwater awards (Details5) - USD ($) $ / shares in Units, $ in Thousands		2 Months Ended	12 Months Ended
	Nov. 01, 2017	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assumptions for equity options granted:
Underlying Equity		$ 20.00	$ 20.00	$ 6.08
Strike Price		$ 20.00	$ 20.00
Dividend Yield (%)			0.00%	0.00%
Volatility (%)				63.00%
Expected Term (Years)				5 years
Minimum
Assumptions for equity options granted:
Strike Price				$ 14.33
Volatility (%)			46.60%
Expected Term (Years)			4 years
Maximum
Assumptions for equity options granted:
Strike Price				$ 20.61
Volatility (%)			46.80%
Expected Term (Years)			6 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense			$ 500	$ 0	$ 0
Unrecognized equity-based compensation expense		$ 100	$ 100
Rockwater Merger
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of Rockwater share-based awards attributed to pre-acquisition service	$ 12,529
Assumptions for equity options granted:
Underlying Equity		$ 16.36	$ 16.36
Dividend Yield (%)			0.00%
Risk free rate(%), minimum			1.10%
Risk free rate(%), maximum			2.20%
Volatility (%)			45.00%
Rockwater Merger \| Minimum
Assumptions for equity options granted:
Strike Price		5.68	$ 5.68
Expected Term (Years)			0 years
Rockwater Merger \| Maximum
Assumptions for equity options granted:
Strike Price		$ 34.41	$ 34.41
Expected Term (Years)			8 years 4 months 24 days
Rockwater Merger \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized equity-based compensation expense		$ 6,600	$ 6,600
Weighted-average period for recognition (in years)			1 year 4 months 24 days
Total fair value of restricted stock awards and stock options that vested		$ 500
Selling, general and administrative \| Rockwater Merger
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense			$ 5,200