Debt - Schedule of Debt and Lines of Credit (Details) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	May 31, 2025 USD ($) extensionOption	Oct. 31, 2022 USD ($)	Mar. 31, 2026 USD ($) lineOfCredit	Dec. 31, 2025 USD ($) lineOfCredit
Debt Instrument [Line Items]
Unsecured debt, net			$ 6,017,550	$ 6,015,921
Mortgage notes payable, net			784,286	784,348
Total debt, net			6,806,496	6,800,269
Debt instrument face amount			600,000
Essex Portfolio, L.P.
Debt Instrument [Line Items]
Unsecured debt, net			6,017,550	6,015,921
Mortgage notes payable, net			784,286	784,348
Unsecured Term Loan 0.850%, Due May 2028
Debt Instrument [Line Items]
Number of extension options (in extensions) | extensionOption	2
Extension period	1 year
Commerical Paper Program | Commercial Paper
Debt Instrument [Line Items]
Debt instrument face amount			750,000
Unamortized debt issuance expense			$ 400
Debt instrument, term			397 days
Lines of credit
Debt Instrument [Line Items]
Lines of credit			$ 4,660	$ 0
Weighted average interest rate			4.60%	4.80%
Commercial Paper
Debt Instrument [Line Items]
Commercial paper			$ 0	$ 0
Weighted average interest rate			0.00%	0.00%
Mortgage notes payable, net
Debt Instrument [Line Items]
Mortgage notes payable, net			$ 784,286	$ 784,348
Weighted average interest rate			4.10%	4.40%
Weighted average maturity			7 years 8 months 12 days
Unamortized discount (premium), net			$ 100	$ 200
Unamortized debt issuance expense			$ 2,400	$ 2,500
Weighted average interest rate on fixed rate unsecured bonds public offering
Debt Instrument [Line Items]
Weighted average interest rate			3.70%	3.70%
Unsecured debt
Debt Instrument [Line Items]
Unsecured debt, net			$ 6,017,550	$ 6,015,921
Weighted average interest rate			4.00%	4.10%
Unsecured debt | Term Loan, Variable Rate
Debt Instrument [Line Items]
Unsecured debt, net			$ 597,098	$ 596,668
Weighted average maturity			4 years 6 months
Unsecured debt | Bonds public offering - fixed rate, net
Debt Instrument [Line Items]
Unsecured debt, net			$ 5,420,452	5,419,253
Weighted average maturity			6 years 9 months 18 days
Unamortized discount (premium), net			$ 3,300	3,600
Unamortized debt issuance expense			29,100	30,400
Unsecured debt | Unsecured Term Loan 0.850%, Due May 2028
Debt Instrument [Line Items]
Debt instrument face amount	$ 300,000
Interest rate	0.85%
Unsecured debt | Unsecured Term Loan 0.850%, Due May 2028 | Maximum
Debt Instrument [Line Items]
Debt instrument face amount	$ 600,000
Unsecured debt | Unsecured Term Loan 0.850% Due January 2031
Debt Instrument [Line Items]
Debt instrument face amount		$ 300,000
Interest rate	4.00%	4.00%
Basis spread on variable rate		0.85%
Unsecured debt | New Credit Facility | Lines of credit
Debt Instrument [Line Items]
Debt instrument face amount			$ 1,580,000	1,580,000
Basis spread on variable rate			0.775%
Unamortized debt issuance expense			$ 7,000	$ 7,300
Numbers of line of credit | lineOfCredit			2	2
Aggregate borrowing capacity			$ 1,500,000
Debt instrument, variable interest rate, type [extensible enumeration]			Secured Overnight Financing Rate (SOFR) [Member]
Unsecured debt | Working capital line of credit | Lines of credit
Debt Instrument [Line Items]
Basis spread on variable rate			0.775%
Aggregate borrowing capacity			$ 75,000