EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Basic earnings per share [Abstract]
Income available to common stockholders									$ 14,819	$ 12,174	$ 12,446
Weighted average common shares outstanding (in shares)									10,658,173	10,539,271	8,978,972
Earnings per share (in dollars per share)	$ 0.35	$ 0.33	$ 0.37	$ 0.34	$ 0.32	$ 0.30	$ 0.25	$ 0.29	$ 1.39	$ 1.16	$ 1.38
Diluted earnings per share [Abstract]
Income available to common stockholders									$ 14,819	$ 12,174	$ 12,446
Weighted average common shares outstanding (in shares)									10,658,173	10,539,271	8,978,972
Add dilutive effects of potential additional common stock (in shares)									77,918	64,248	229,863
Weighted average common and dilutive potential Common shares outstanding (in shares)									10,736,091	10,603,519	9,208,835
Earnings per share assuming dilution (in dollars per share)	$ 0.35	$ 0.32	$ 0.36	$ 0.34	$ 0.32	$ 0.30	$ 0.25	$ 0.29	$ 1.38	$ 1.15	$ 1.35
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities not considered in computing diluted earnings per share (in shares)									0	0	25,850