EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
EARNINGS PER SHARE
Net income	$ 8,841	$ 8,854	$ 18,012	$ 17,480
Dividends paid on and earnings allocated to participating securities	(182)	(181)	(360)	(351)
Income attributable to common stock	$ 8,659	$ 8,673	$ 17,652	$ 17,129
Weighted average common shares outstanding, including participating securities	19,781	17,507	19,725	17,493
Weighted average participating securities (in shares)	(410)	(358)	(401)	(356)
Weighted average common shares outstanding	19,371	17,149	19,324	17,137
Basic earnings per common share (in dollars per share)	$ 0.45	$ 0.51	$ 0.91	$ 1
Income attributable to common stock	$ 8,659	$ 8,673	$ 17,652	$ 17,129
Impact of assumed conversions - interest on 8.5% trust preferred securities		223	32	444
Income attributable to common stock including assumed conversions	$ 8,659	$ 8,896	$ 17,684	$ 17,573
Weighted average common shares outstanding	19,371	17,149	19,324	17,137
Incremental shares from assumed conversions of options and restricted stock units	23	14	20	9
Incremental shares from assumed conversions of 8.5% trust preferred securities		530	35	523
Weighted average common and equivalent shares outstanding	19,394	17,693	19,379	17,669
Diluted earnings per common share (in dollars per share)	$ 0.45	$ 0.5	$ 0.91	$ 0.99