Real Estate Disposition Activities (Details) ft² in Thousands, $ in Thousands	3 Months Ended			12 Months Ended
	Dec. 31, 2023 USD ($) ft² community residential_condominium home	Sep. 30, 2023 USD ($) home	Jun. 30, 2023 USD ($) home	Dec. 31, 2023 USD ($) ft² residential_condominium community home	Dec. 31, 2022 USD ($) ft² residential_condominium home	Dec. 31, 2021 USD ($) ft² home residential_condominium
Summary of income from discontinued operations
Gains (Losses) on Sales of Investment Real Estate				$ 287,424	$ 555,558	$ 602,235
Number of communities held for sale | community	0			0
Number of residential condominiums sold | residential_condominium				6	40	53
Number of residential condominiums remaining to be sold | residential_condominium	2			2
Other selling, general and administrative expense				$ 389	$ 2,129	$ 4,087
Inventory, real estate	$ 6,603			6,603	32,532
The Park Loggia
Summary of income from discontinued operations
Net cash proceeds				$ 25,387	126,848	135,458
Number of residential units in development | residential_condominium	172			172
Commercial square feet | ft²	66			66
Gain on for-sale condominiums				$ (73)	$ 2,217	$ 3,110
eaves Daly City
Summary of income from discontinued operations
Number of apartment homes sold | home			195
Gross sales price			$ 67,000
Net cash proceeds			$ 66,646
Avalon at Newton Highlands
Summary of income from discontinued operations
Number of apartment homes sold | home			294
Gross sales price			$ 170,000
Net cash proceeds			$ 167,665
Avalon Columbia Pike
Summary of income from discontinued operations
Number of apartment homes sold | home		269
Gross sales price		$ 105,000
Net cash proceeds		$ 103,032
Commercial square feet | ft²	27			27
Avalon Mamaroneck
Summary of income from discontinued operations
Number of apartment homes sold | home	229
Gross sales price	$ 104,000
Net cash proceeds	$ 102,230
Other real estate
Summary of income from discontinued operations
Gross sales price				$ 0
Net cash proceeds				$ 636
Wholly owned properties
Summary of income from discontinued operations
Number of apartment homes sold | home				987	2,062	2,404
Gross sales price				$ 446,000	$ 953,135	$ 875,058
Net cash proceeds				$ 440,209	$ 934,117	$ 850,230
Commercial square feet | ft²	27			27	0	30