EARNINGS PER COMMON SHARE - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator
Net income attributable to common stockholders	$ 148,141	$ 60,034	$ 69,171
Denominator
Basic weighted average common shares and common equivalents (in shares)	105,621,242	65,284,251	62,235,014
Dilutive stock options and restricted stock units (in shares)	221,192	236,421	225,225
Dilutive weighted average common shares (in shares)	105,842,434	65,520,672	62,460,239
Net income attributable to common stockholders, per:
Basic common share (in dollars per share)	$ 1.40	$ 0.92	$ 1.11
Diluted common share (in dollars per share)	$ 1.40	$ 0.92	$ 1.11