EQUITY-BASED COMPENSATION - Time-Based Restricted Stock Awards (Details) - Restricted Stock Awards - Time-Based - USD ($) $ / shares in Units, $ in Thousands								12 Months Ended
	Apr. 18, 2017	Mar. 06, 2017	Sep. 02, 2016	Mar. 08, 2016	Feb. 24, 2016	Apr. 24, 2015	Mar. 03, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Non-vested at the beginning of year (in shares)								357,845	250,011
Granted (in shares)								156,318	192,123
Vested (in shares)								(120,366)	(82,869)
Forfeited (in shares)								(2,320)	(1,420)
Non-vested at end of year (in shares)								391,477	357,845	250,011
Weighted Average Grant Date Fair Value
Non-vested at beginning of year (in dollars per share)								$ 11.90	$ 12.03
Granted (in dollars per share)								15.52	11.36
Vested (in dollars per share)								11.29	11.06
Forfeited (in dollars per share)								13.70	10.27
Non-vested at end of year (in dollars per share)								$ 13.52	$ 11.90	$ 12.03
Aggregate Current Value
Non-vested outstanding								$ 5,962
Total fair value of awards vested								$ 1,400	$ 900	$ 1,000
Employees
Equity-based compensation
Vesting period		4 years			4 years
Number of Shares
Granted (in shares)		16,079	406		22,010
Employees | Period one
Equity-based compensation
Vesting percentage		20.00%			20.00%
Employees | Period two
Equity-based compensation
Vesting percentage		20.00%	20.00%		20.00%
Employees | Period three
Equity-based compensation
Vesting percentage		20.00%	20.00%		20.00%
Employees | Period four
Equity-based compensation
Vesting percentage		40.00%			40.00%
Executive officers
Number of Shares
Granted (in shares)	20,215	120,024		169,707		16,930
Executive officers | Period one
Equity-based compensation
Vesting percentage	25.00%			25.00%
Executive officers | Period two
Equity-based compensation
Vesting percentage	25.00%			25.00%
Executive officers | Period three
Equity-based compensation
Vesting percentage	50.00%			50.00%
Executive officers and management
Equity-based compensation
Vesting period							3 years
Number of Shares
Granted (in shares)							149,410
Executive officers and management | Continued service on March 9, 2018, or upon a change in control
Number of Shares
Granted (in shares)							37,230
Executive officers and management | Period one
Equity-based compensation
Vesting percentage							25.00%
Executive officers and management | Period two
Equity-based compensation
Vesting percentage							25.00%
Executive officers and management | Period three
Equity-based compensation
Vesting percentage							50.00%