Segments - Schedule of Reconciliation of NOI to Net (Loss) Income Attributable to Common Stockholders (Details) - USD ($) $ 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
Segment Reporting [Abstract]
NOI									$ 475,601	$ 494,009	$ 486,984
Fee income									28,070	22,744	18,629
Depreciation and amortization expense									(235,200)	(240,104)	(240,868)
General and administrative expenses									(64,917)	(68,556)	(57,563)
NOI from unconsolidated joint ventures									(48,631)	(22,409)	(20,730)
(Loss) income from unconsolidated joint ventures									(18,619)	(4,706)	3,468
Interest and other income, net									4,490	9,844	7,936
Interest and debt expense									(144,208)	(156,679)	(147,653)
Loss on early extinguishment of debt										(11,989)
Adjustments related to discontinued operations (including impairments and gain or loss on sale of real estate)									(8,390)	(15,292)	(31,909)
Other, net									(824)	(2,342)	(1,740)
Net (loss) income before income taxes									(12,628)	4,520	16,554
Income tax expense									(1,493)	(312)	(3,139)
(Loss) income from continuing operations, net									(14,121)	4,208	13,415
(Loss) income from discontinued operations, net									(5,075)	(33,811)	5,578
Net (loss) income									(19,196)	(29,603)	18,993
Consolidated joint ventures									(9,257)	(11,022)	(8,182)
Consolidated real estate fund									1,450	(313)	(720)
Operating Partnership									2,299	4,039	(944)
Net (loss) income attributable to common stockholders	$ (14,824)	$ (6,958)	$ (6,270)	$ 3,348	$ (50,145)	$ 7,082	$ 2,455	$ 3,709	$ (24,704)	$ (36,899)	$ 9,147