Earnings per Share ("EPS") (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator
Net income (loss)	$ 8,843	$ (34,381)
Less net income (loss) attributable to noncontrolling interests	1,019	(808)
Net income (loss) attributable to the Company	7,824	(33,573)
Allocation of earnings to participating securities	(281)	(244)
Numerator for basic and diluted EPS—net income attributable to common stockholders	$ 7,543	$ (33,817)
Denominator
Denominator for basic EPS—weighted average number of common shares outstanding (in shares)	141,262,000	141,024,000
Effect of dilutive securities:
Share and unit-based compensation plans (in shares)	0	26,000
Denominator for diluted EPS—weighted average number of common shares outstanding (in shares)	141,262,000	141,050,000
EPS—net income (loss) attributable to common stockholders:
Basic (in dollars per share)	$ 0.05	$ (0.24)
Diluted (in dollars per share)	$ 0.05	$ (0.24)
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
Partnership unit
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from Diluted EPS (in shares)	10,415,190	10,291,217