SUMMARY OF QUARTERLY FINANCIAL INFORMATION (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 51,156	$ 47,660	$ 49,511	$ 46,685	$ 44,102	$ 41,085	$ 40,808	$ 42,291	$ 195,012	$ 168,286	$ 114,987
Income from continuing operations	9,341	28,564	11,365	21,595	7,576	8,893	7,967	9,590	70,865	34,026	23,619
Income from discontinued operations attributable to Common Shareholders	100	0	99	0	4,675	591	790	33	199	6,089	16,087
Net income attributable to Common Shareholders	$ 9,441	$ 28,564	$ 11,464	$ 21,595	$ 12,251	$ 9,484	$ 8,757	$ 9,623	$ 71,064	$ 40,115	$ 39,706
Net income attributable to Common Shareholders per Common Share - basic:
Income from continuing operations (in dollars per share)	$ 0.13	$ 0.47	$ 0.19	$ 0.38	$ 0.14	$ 0.16	$ 0.14	$ 0.18	$ 1.18	$ 0.61	$ 0.51
Income from discontinued operations (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.08	$ 0.01	$ 0.02	$ 0.00	$ 0.00	$ 0.11	$ 0.34
Net income per share (in dollars per share)	$ 0.13	$ 0.47	$ 0.19	$ 0.38	$ 0.22	$ 0.17	$ 0.16	$ 0.18	$ 1.18	$ 0.72	$ 0.85
Net income attributable to Common Shareholders per Common Share - diluted:
Income from continuing operations (in dollars per share)	$ 0.15	$ 0.47	$ 0.19	$ 0.38	$ 0.14	$ 0.16	$ 0.14	$ 0.18	$ 1.18	$ 0.61	$ 0.51
Income from discontinued operations (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.08	$ 0.01	$ 0.02	$ 0.00	$ 0.00	$ 0.11	$ 0.34
Net income per share (in dollars per share)	$ 0.15	$ 0.47	$ 0.19	$ 0.38	$ 0.22	$ 0.17	$ 0.16	$ 0.18	$ 1.18	$ 0.72	$ 0.85
Cash dividends declared per Common Share (in dollars per share)	$ 0.54	$ 0.23	$ 0.23	$ 0.23	$ 0.23	$ 0.21	$ 0.21	$ 0.21	$ 1.23	$ 0.86	$ 0.72