Related Party Arrangements (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Related Party Arrangements
Management, development and other fees	$ 3,084,000	$ 3,819,000	$ 4,960,000
Compensation expense	25,100,000	21,110,000	24,885,000
Property and construction management roles
Related Party Arrangements
Outstanding receivables	3,964,000	5,408,000
Non-employee directors
Related Party Arrangements
Payable to related parties	90,000
Payable to related parties in quarterly installments	22,500
Non-employee directors | Restricted stock and deferred stock awards
Related Party Arrangements
Payable to related parties	170,000
Compensation expense	1,981,000	1,819,000	1,725,000
Amount of deferred compensation	696,000	$ 614,000	$ 594,000
Lead Independent Director
Related Party Arrangements
Payable to related parties	30,000
Payable to related parties in quarterly installments	7,500
Non-employee director serving as the chairperson of the Audit Committee
Related Party Arrangements
Payable to related parties	25,000
Payable to related parties in quarterly installments	6,250
Non-employee director serving as a chairperson of the Compensation Committee
Related Party Arrangements
Payable to related parties	20,000
Payable to related parties in quarterly installments	5,000
Non-employee director serving as a chairperson of the Nominating and Corporate Governance and Investment and Finance Committees
Related Party Arrangements
Payable to related parties	15,000
Payable to related parties in quarterly installments	$ 3,750