Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates - Schedule of Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Combined and Condensed Balance Sheets
Real estate under development	$ 217,620	$ 247,349
Other assets	159,592	173,809
Total assets	4,089,612	4,186,882	$ 4,328,748
Total liabilities and equity	4,089,612	4,186,882
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	14,896	15,616
Investments in and advances to unconsolidated affiliates	258,063	249,807
Unconsolidated Affiliates
Combined and Condensed Balance Sheets
Rental property, net	556,800	563,997
Real estate under development	12,900	14,517
Other assets	63,060	61,969
Total assets	632,760	640,483
Mortgage notes payable	507,111	512,490
Other liabilities	72,577	74,872
Partners’ equity	53,072	53,121
Total liabilities and equity	632,760	640,483
Company's share of accumulated equity	100,237	100,767
Basis differential	54,320	55,017
Deferred fees, net of portion related to the Company's interest	3,962	3,565
Amounts receivable/payable by the Company	467	363
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	158,986	159,712
Investments carried at fair value or cost	84,181	74,479
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	14,896	15,616
Investments in and advances to unconsolidated affiliates	$ 258,063	$ 249,807