Real Estate Disposition Activities (Details) ft² in Thousands	3 Months Ended			9 Months Ended		33 Months Ended
	Sep. 30, 2022 USD ($) home ft² residential_condominium community	Mar. 31, 2022 USD ($) home	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) ft² residential_condominium community	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) ft² residential_condominium community	Dec. 31, 2021 USD ($)
Summary of income from discontinued operations
Gain on sale of communities	$ 318,289,000		$ 58,000	$ 467,493,000	$ 388,354,000
Number of communities held for sale | community	1			1		1
Number of residential condominium units sold | residential_condominium	10			38		161
Gain on for-sale condominiums				$ 2,113,000	2,051,000
Number of residential condominiums remaining to be sold | residential_condominium	11			11		11
Other selling, general and administrative expense	$ 340,000		$ 1,187,000	$ 1,644,000	$ 3,453,000
For-sale condominium inventory	38,509,000			38,509,000		$ 38,509,000	$ 146,535,000
The Park Loggia
Summary of income from discontinued operations
Proceeds from sale of real estate	$ 38,991,000			$ 120,328,000
Number of residential condominium units | residential_condominium	172			172		172
Square feet of commercial space | ft²	66			66		66
Gain on for-sale condominiums	$ 644,000			$ 2,113,000
Avalon West Long Branch
Summary of income from discontinued operations
Number of apartment homes sold | home		180
Proceeds from sale of real estate		$ 75,000,000
Gain on sale of communities		$ 56,434,000
Avalon Ossining
Summary of income from discontinued operations
Number of apartment homes sold | home		168
Proceeds from sale of real estate		$ 70,000,000
Gain on sale of communities		$ 40,512,000
Avalon East Norwalk
Summary of income from discontinued operations
Number of apartment homes sold | home		240
Proceeds from sale of real estate		$ 90,000,000
Gain on sale of communities		$ 51,762,000
Avalon Green I, Avalon Green II and Avalon Green III
Summary of income from discontinued operations
Number of apartment homes sold | home	617
Proceeds from sale of real estate	$ 306,000,000
Gain on sale of communities	$ 196,466,000
Avalon Del Mar Station
Summary of income from discontinued operations
Number of apartment homes sold | home	347
Proceeds from sale of real estate	$ 172,300,000
Gain on sale of communities	$ 77,141,000
Avalon Sharon
Summary of income from discontinued operations
Number of apartment homes sold | home	156
Proceeds from sale of real estate	$ 65,650,000
Gain on sale of communities	$ 44,355,000