Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates - Schedule of Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Combined and Condensed Balance Sheets
Real estate under development	$ 219,037	$ 247,349
Other assets	174,750	173,809
Total assets	4,244,645	4,186,882	$ 4,251,408
Total liabilities and equity	4,244,645	4,186,882
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	15,456	15,616
Investments in and advances to unconsolidated affiliates	305,668	249,807
Unconsolidated Affiliates
Combined and Condensed Balance Sheets
Rental property, net	557,892	563,997
Real estate under development	10,768	14,517
Other assets	63,461	61,969
Total assets	632,121	640,483
Mortgage notes payable	507,396	512,490
Other liabilities	71,937	74,872
Partners’ equity	52,788	53,121
Total liabilities and equity	632,121	640,483
Company's share of accumulated equity	100,015	100,767
Basis differential	54,065	55,017
Deferred fees, net of portion related to the Company's interest	4,036	3,565
Amounts receivable/payable by the Company	527	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	158,643	159,712
Investments carried at fair value or cost	131,569	74,479
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	15,456	15,616
Investments in and advances to unconsolidated affiliates	$ 305,668	$ 249,807