COMMON STOCK ACTIVITY (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares outstanding at beginning of year (in shares)	38,925,953
Common stock offerings (in shares)	709,924	2,388,342	1,706,474
Dividend reinvestment plan (in shares)	0	1,893	1,844
Shares outstanding at end of year (in shares)	39,676,828	38,925,953
Common shares, issued	39,676,828	38,925,953
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares outstanding at beginning of year (in shares)	38,925,953	36,501,356	34,758,167
Common stock offerings (in shares)	709,924	2,388,342	1,706,474
Dividend reinvestment plan (in shares)	0	1,893	1,844
Incentive restricted stock granted (in shares)	69,446	59,943	50,217
Incentive restricted stock forfeited (in shares)	(440)	(3,010)	0
Director common stock awarded (in shares)	8,182	6,384	8,478
Director restricted stock granted (in shares)	208	0	0
Restricted stock withheld for tax obligations (in shares)	(36,445)	(28,955)	(23,824)
Shares outstanding at end of year (in shares)	39,676,828	38,925,953	36,501,356
Additional Paid-in Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from common stock issuances	$ 92,663,000	$ 284,710,000	$ 157,319,000
Common shares, issued	709,924	2,388,342	1,706,474