Related Party Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Arrangements
Management, development and other fees	$ 695	$ 1,017	$ 2,380	$ 2,950
Compensation expense			19,965	17,385
Unconsolidated real estate entities
Related Party Arrangements
Outstanding receivables	3,374		3,374		$ 5,408
Non Employee Director | Restricted stock and deferred stock awards
Related Party Arrangements
Compensation expense	516	$ 459	1,457	$ 1,360
Amount of deferred compensation	$ 1,119		$ 1,119		$ 614