SHAREHOLDERS EQUITY - Stock based compensation - Time Vesting Units (Details) - Time Vesting Units $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value \| $ / shares	$ 27.15
Granted (in shares) \| shares	25,087
Stock-based compensation expense \| $	$ 0.7
Unrecognized compensation expense \| $	$ 3.9
Unrecognized compensation expense recognition period (in years)	3 years 9 months
Third and fifth anniversaries
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period (in years)	5 years
Vesting Percentage	50.00%
Second and fourth anniversaries
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period (in years)	4 years
Vesting Percentage	50.00%
Granted (in shares) \| shares	4,500

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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- Definition

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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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

+ References

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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

Percentage of vesting of share-based compensation awards.

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