SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ACCOUNTING POLICIES - Schedule of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income applicable to common stockholders									$ 55,130	$ 72,078	$ 59,903
Weighted average shares outstanding, basic (in shares)									37,705,179	36,938,943	36,478,759
Weighted average effect of dilutive securities (in shares)									114,438	1,612,765	1,964,185
Weighted average shares outstanding, diluted (in shares)									37,819,617	38,551,708	38,442,944
Per share data
Basic (in dollars per share)	$ 0.40	$ 0.19	$ 0.42	$ 0.46	$ 0.60	$ 0.44	$ 0.55	$ 0.34	$ 1.46	$ 1.95	$ 1.64
Diluted (in dollars per share)	$ 0.40	$ 0.18	$ 0.42	$ 0.46	$ 0.57	$ 0.42	$ 0.53	$ 0.33	$ 1.46	$ 1.87	$ 1.56