EQUITY-BASED COMPENSATION - Stock options (Details) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($) $ / shares shares
Stock options
Equity-based compensation
Number of outstanding shares (in shares) \| shares	235,000
Number of exercisable shares (in shares) \| shares	235,000
Weighted average exercise price, outstanding (in dollars per share) \| $ / shares	$ 9.75
Weighted average exercise price, exercisable (in dollars per share) \| $ / shares	$ 9.75
Weighted Average Remaining Contractual Terms, outstanding	3 years 8 months
Weighted Average Remaining Contractual Terms, exercisable	3 years 8 months
Aggregate intrinsic value, outstanding \| $	$ 2.1
Aggregate intrinsic value, exercisable \| $	$ 2.1
Minimum
Equity-based compensation
Stock options term	5 years
Maximum
Equity-based compensation
Stock options term	10 years

Share-based Compensation Arrangement by Share-based Payment Award, Options, Term

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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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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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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 options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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