Investments in Unconsolidated Real Estate Ventures - Condensed Combined Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Combined balance sheet information:
Real estate, net	$ 2,453,106		$ 2,453,106		$ 2,493,961
Other assets, net	287,903		287,903		291,092
Total assets	2,741,009		2,741,009		2,785,053
Borrowings, net	1,325,051		1,325,051		1,187,856
Other liabilities, net	159,091		159,091		168,243
Total liabilities	1,484,142		1,484,142		1,356,099
Total equity	1,256,867		1,256,867		1,428,954
Total liabilities and equity	2,741,009		2,741,009		$ 2,785,053
Combined income statement information:
Total revenue	45,314	$ 74,796	114,893	$ 134,787
Operating income	(25,232)	10,542	(25,714)	10,109
Net loss	(35,901)	$ (1,460)	(54,066)	$ (16,687)
Landmark | Woodglen
Combined income statement information:
Equity Method Investment, Realized Gain (Loss) on Disposal	$ 16,400		$ 16,400