Significant Transactions During The Three Months Ended March 31, 2020 and Subsequent Events (Details)	1 Months Ended			3 Months Ended
	Apr. 30, 2020 USD ($) extension	Mar. 31, 2020 USD ($)	Jan. 31, 2020 USD ($) community apartment	Mar. 31, 2020 USD ($) shares	Mar. 31, 2019 USD ($)	Feb. 29, 2020 USD ($)
Other Commitments [Line Items]
Gain on remeasurement of co-investment				$ 234,694,000	$ 31,535,000
Commitments to acquire equity method investment				$ 91,400,000
Preferred return rate				11.30%
Notes receivable, term of extension option		2 years
Common Stock
Other Commitments [Line Items]
Shares repurchased during period (in shares) | shares				776,261
Shares repurchased during period, value				$ 176,300,000
Purchase authority remaining under stock repurchase plan		$ 73,700,000		73,700,000
Stock repurchase plan amount		250,000,000.0		250,000,000.0
CPPIB interest
Other Commitments [Line Items]
Investment interest acquired			45.00%
Value of property held by acquired investment			$ 1,000,000,000.0
Gain on remeasurement of co-investment			234,700,000
Promote income			6,500,000
Joint venture that holds property in Los Angeles, CA
Other Commitments [Line Items]
Proceeds from partial redemption of co-investment		11,300,000
Early redemption fee		200,000
Property Located In Anaheim, California
Other Commitments [Line Items]
Proceeds from redemption of notes receivable			$ 16,900,000
Multifamily Development Communities In Los Angeles, California
Other Commitments [Line Items]
Notes receivable, commitment to fund, amount		$ 15,000,000.0		$ 15,000,000.0
Notes receivable, interest rate		10.50%		10.50%
Apartment Building | CPPIB interest
Other Commitments [Line Items]
Number of communities held by acquired investment | community			6
Number of units held by acquired investment | apartment			2,020
Essex Portfolio, L.P.
Other Commitments [Line Items]
Gain on remeasurement of co-investment				$ 234,694,000	$ 31,535,000
Essex Portfolio, L.P. | Senior Notes | 2032 Notes
Other Commitments [Line Items]
Debt issued						$ 500,000,000.0
Debt coupon rate						2.65%
Debt offering price, percentage of par value						99.628%
Repayments of secured debt				$ 100,300,000
Affiliated Entity | Related party bridge loan - Wesco V
Other Commitments [Line Items]
Proceeds from redemption of notes receivable			$ 85,800,000
Subsequent Event | Unsecured Term Loan
Other Commitments [Line Items]
Debt issued	$ 200,000,000.0
Number of extension options (in extensions) | extension	2
Extension period	12 months
Prepayment of debt	$ 169,600,000
Subsequent Event | LIBOR | Unsecured Term Loan
Other Commitments [Line Items]
Basis spread on variable rate	1.20%