Segment Information - Reconciliation of Consolidated Net Income to Consolidated NOI (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting [Abstract]
Net income (loss)	$ (175)	$ 6,964	$ 4,020	$ 8,087	$ 6,789	$ 12,107
Plus:
Interest expense	15,490		20,191		31,783	40,200
Interest expense - amortization of deferred financing costs	709		731		1,418	1,480
Depreciation and amortization	42,785		49,743		83,128	101,781
General and administrative expenses	8,356		8,343		14,940	16,904
Equity in loss of unconsolidated real estate ventures	7,240		2,203		14,164	4,094
Less:
Interest and investment income	1,677		445		3,351	1,020
Income tax (provision) benefit	(15)		230		(34)	226
Net gain on disposition of real estate	68		0		142	2,586
Net gain on sale of undepreciated real estate	0		201		1,993	201
Net operating income (loss)	$ 72,675		$ 84,355		$ 146,770	$ 172,533