Earnings per Share ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator
Net income (loss)	$ 13,947	$ 8,866	$ 22,790	$ (25,515)
Less net (loss) income attributable to noncontrolling interests	(1,787)	1,050	(768)	242
Net income (loss) attributable to the Company	15,734	7,816	23,558	(25,757)
Allocation of earnings to participating securities	(291)	(304)	(573)	(547)
Numerator for basic and diluted EPS—net income attributable to common stockholders	$ 15,443	$ 7,512	$ 22,985	$ (26,304)
Denominator
Weighted Average Number of Shares Outstanding, Diluted	141,344,000	141,137,000	141,303,000	141,081,000
EPS—net income (loss) attributable to common stockholders:
Basic (in dollars per share)	$ 0.11	$ 0.05	$ 0.16	$ (0.19)
Diluted (in dollars per share)	$ 0.11	$ 0.05	$ 0.16	$ (0.19)
Convertible non-participating preferred units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from Diluted EPS (in shares)	90,619	90,619	90,619	90,619
Partnership unit
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from Diluted EPS (in shares)	10,415,278	10,397,726	10,415,234	10,344,766