CALCULATION OF WEIGHTED AVERAGE SHARES OUTSTANDING FOR EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended							9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net income	$ 49,884	$ 54,382	$ 46,855	$ 38,957	$ 36,548	$ 23,541	$ 16,882	$ 151,121	$ 76,971
Basic weighted average shares outstanding	34,446,510				35,193,109			34,716,914	35,285,567
Dilutive effect of unvested restricted stock	222,982				123,570			295,314	239,204
Diluted weighted shares outstanding	34,669,492				35,316,679			35,012,228	35,524,771
Earnings per common share
Basic	$ 1.45				$ 1.04			$ 4.35	$ 2.18
Diluted	$ 1.44				$ 1.03			$ 4.32	$ 2.17