Quarterly Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								5 Months Ended	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 40,404	$ 34,870	$ 29,683	$ 24,484	$ 19,694	$ 14,161	$ 11,447	$ 8,032		$ 129,441	$ 53,334	$ 17,045
Operating (loss) income	5,883	3,812	3,271	(459)	1,967	(2,311)	(626)	(3,575)		12,507	(4,545)	(2,634)
Net income	5,909	3,983	3,297	(448)	1,991	(2,251)	(600)	(3,558)	$ (2,060)	12,741	(4,418)	(2,636)
Net (loss) income attributable to common shareholders	$ 5,146	$ 3,404	$ 2,571	$ (522)	$ 1,711	$ (2,094)	$ (561)	$ (3,093)		$ 10,599	$ (4,037)	$ (1,661)
Earnings per share – basic:
Earnings per share - basic (in dollars per share)	$ 0.06	$ 0.05	$ 0.04	$ (0.01)	$ 0.04	$ (0.06)	$ (0.02)	$ (0.15)		$ 0.15	$ (0.12)	$ (0.13)
Basic (in shares)	83,761,536	71,034,747	70,376,959	65,649,478	48,145,409	36,313,644	26,163,982	21,298,597		72,750,724	33,063,093	12,883,917
Earnings per share – diluted:
Earnings per share - diluted (in dollars per share)	$ 0.06	$ 0.05	$ 0.04	$ (0.01)	$ 0.04	$ (0.06)	$ (0.02)	$ (0.15)		$ 0.15	$ (0.12)	$ (0.13)
Diluted (in shares)	87,911,097	75,104,821	74,267,284	65,649,478	48,354,493	36,313,644	26,163,982	21,298,597		76,792,073	33,063,093	12,883,917