COMMON STOCK ACTIVITY (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares outstanding at beginning of year (in shares)	34,758,167
Common stock offerings (in shares)	1,706,474	1,370,457	875,052
Stock Issued During Period, Value, New Issues	$ 157,319	$ 109,207	$ 59,283
Dividend reinvestment plan (in shares)	1,844	2,744	3,326
Shares outstanding at end of year (in shares)	36,501,356	34,758,167
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares outstanding at beginning of year (in shares)	34,758,167	33,332,213	32,421,460
Common stock offerings (in shares)	1,706,474	1,370,457	875,052
Dividend reinvestment plan (in shares)	1,844	2,744	3,326
Incentive restricted stock granted (in shares)	50,217	93,285	80,529
Incentive restricted stock forfeited (in shares)	0	(16,000)	(910)
Director common stock awarded (in shares)	8,478	8,881	10,072
Stock issued during period, restricted stock awarded to directors	0	282	0
Restricted stock withheld for tax obligations (in shares)	(23,824)	(33,695)	(57,316)
Shares outstanding at end of year (in shares)	36,501,356	34,758,167	33,332,213
Additional Paid-in Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, New Issues	$ 157,318	$ 109,207	$ 59,283