EMPLOYEE BENEFIT PLANS - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Employee contribution on compensation, maximum	100.00%
Employer contribution match on compensation	100.00%
Percentage of employees' annual contribution, eligible for employers match	4.00%
401(k) plan expense	$ 3.1	$ 3.9	$ 3.6
Restricted Stock \| 2013 Omnibus Stock Incentive Plan
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Award vesting period	5 years
Restricted stock awards issued under Employee Equity Ownership Plan	35,016	98,693	58,073
Unvested restricted stock awards (in shares)	64,755
Unrecognized stock-based compensation expense	$ 1.1

Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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