EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Unvested service-based restricted shares (in shares)	700			700			700	700
Numerator:
Net income	$ 14,510	$ 14,460	$ 11,502	$ 15,902	$ 17,011	$ 15,508	$ 40,473	$ 48,422
Less: Income allocated to participating securities	(156)			(172)			(443)	(525)
Net income available to common stockholders	$ 14,354			$ 15,730			$ 40,030	$ 47,897
Denominator:
Weighted average shares - basic (in shares)	66,960			66,562			66,858	66,476
Performance-based restricted stock awards (in shares)	0			36			0	31
Weighted average shares - diluted (in shares)	66,960			66,598			66,858	66,507
Basic net income per share (in usd per share)	$ 0.21			$ 0.24			$ 0.60	$ 0.72
Diluted net income per share (in usd per share)	$ 0.21			$ 0.24			$ 0.60	$ 0.72