Unconsolidated Affiliates and Noncontrolling Interests - Unconsolidated Affiliates (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
ASSETS
Investment in real estate assets	$ 2,135,627		$ 2,135,627		$ 2,097,088
Accumulated depreciation	(741,802)		(741,802)		(674,275)
Real estate investment net, before development in process	1,393,825		1,393,825		1,422,813
Developments in progress	27,309		27,309		12,569
Net investment in real estate assets	1,421,134		1,421,134		1,435,382
Other assets	150,597		150,597		188,521
Total assets	1,571,731		1,571,731		1,623,903
LIABILITIES
Mortgage and other indebtedness, net	1,252,003		1,252,003		1,319,949
Other liabilities	44,194		44,194		39,777
Total liabilities	1,296,197		1,296,197		1,359,726
OWNERS' EQUITY
The Company	173,340		173,340		191,050
Other investors	102,194		102,194		73,127
Total owners' equity	275,534		275,534		264,177
Total liabilities and owners' equity	1,571,731		1,571,731		$ 1,623,903
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Total revenues	52,867	$ 54,579	162,964	$ 166,843
Net income (loss)	81,300	(85,136)	90,303	(72,585)
Parent Company
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Net income (loss)	$ (1,759)	$ 1,762	$ 3,421	$ 9,869