EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Basic earnings per share
Net income	$ 12,356	$ 9,853	$ 34,048	$ 31,598
Weighted average common shares outstanding (in shares)	24,305,378	24,258,062	24,247,605	24,156,072
Basic earnings per common share (in dollars per share)	$ 0.51	$ 0.41	$ 1.40	$ 1.31
Diluted earnings per share
Net income	$ 12,356	$ 9,853	$ 34,048	$ 31,598
Weighted average common shares outstanding for basic earnings per common share (in shares)	24,305,378	24,258,062	24,247,605	24,156,072
Add: Dilutive effects of restricted stock and options (in shares)	197,243	309,863	192,880	290,569
Average shares and dilutive potential common shares (in shares)	24,502,621	24,567,925	24,440,485	24,446,641
Diluted earnings per common share (in dollars per share)	$ 0.50	$ 0.40	$ 1.39	$ 1.29