EQUITY AND EPS - Computations of Earnings (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operations:
Net income	$ 11,632	$ 10,381	$ 8,490	$ 9,842	$ 12,947	$ 8,215	$ 7,911	$ 9,720	$ 40,345	$ 38,793	$ 37,284
Less: Income attributable to participating securities (unvested shares and units)									261	253	708
Net income attributable to common shareholders and used in Earnings Per Share calculation									$ 40,084	$ 38,540	$ 36,576
Share information:
Basic and diluted weighted average common shares (in shares)									16,937,125	17,012,288	16,866,176
Basic and diluted EPS (in dollars per share)	$ 0.69	$ 0.61	$ 0.50	$ 0.57	$ 0.76	$ 0.48	$ 0.46	$ 0.57	$ 2.37	$ 2.27	$ 2.17
Restricted Stock Units (RSUs)
Share information:
Participating securities (in shares)									110,665	111,365	326,375