Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 438,410	$ 248,239	$ 134,438
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	441,682	453,423	360,592
Amortization of discount on marketable securities and other investments	(14,211)	(12,389)	(9,325)
Amortization of (premium) discount and financing costs, net	(15,234)	(19,361)	(14,672)
Gain on sale of marketable securities and other investments	(5,719)	(598)	(886)
Company's share of gain on the sales of co-investments	(13,046)	0	(6,558)
Earnings from co-investments	(35,652)	(21,861)	(33,335)
Operating distributions from co-investments	60,472	46,608	49,486
Gain on the sales of real estate and land	(154,561)	(47,333)	(46,039)
Equity-based compensation	10,899	6,061	8,740
Loss on early retirement of debt, net	606	6,114	268
Gain on remeasurement of co-investments	0	(34,014)	0
Noncash merger and integration expenses	0	0	9,025
Changes in operating assets and liabilities:
Prepaid expenses, receivables and other assets	(2,328)	267	15,828
Accounts payable and accrued liabilities	1,701	(9,633)	24,233
Other liabilities	(496)	1,887	1,517
Net cash provided by operating activities	712,523	617,410	493,312
Additions to real estate:
Acquisitions of real estate and acquisition related capital expenditures	(315,632)	(515,726)	(387,547)
Redevelopment	(83,927)	(99,346)	(81,429)
Development acquisitions of and additions to real estate under development	(76,455)	(157,900)	(152,766)
Capital expenditures on rental properties	(60,013)	(57,277)	(78,864)
Acquisition of membership interest in co-investments	0	(115,724)	0
Collections of notes and other receivables	4,070	0	76,585
Investments in notes receivable	(24,070)	0	0
Proceeds from insurance for property losses	5,543	16,811	35,547
BRE merger consideration paid	0	0	(555,826)
Proceeds from dispositions of real estate	239,289	319,008	141,189
Contributions to co-investments	(183,989)	(127,879)	(246,006)
Changes in restricted cash and refundable deposits	(14,138)	(14,068)	(36,582)
Purchases of marketable securities	(18,779)	(14,300)	(20,516)
Sales and maturities of marketable securities and other investments	30,458	8,907	8,753
Non-operating distributions from co-investments	76,231	31,938	150,306
Net cash used in investing activities	(421,412)	(725,556)	(1,147,156)
Cash flows from financing activities:
Borrowings under debt agreements	1,265,388	1,345,855	2,093,406
Repayment of debt	(1,018,126)	(1,197,351)	(1,814,020)
Repayment of cumulative redeemable preferred stock	(73,750)	0	0
Retirement of common stock	(1,045)	0	0
Additions to deferred charges	(7,926)	(8,034)	(17,402)
Net proceeds from issuance of common stock	(384)	332,137	531,379
Net proceeds from stock options exercised	18,949	26,540	11,039
Distributions to noncontrolling interest	(25,334)	(21,055)	(17,465)
Redemption of noncontrolling interest	(2,511)	(2,621)	(5,753)
Common and preferred stock dividends paid	(411,134)	(367,257)	(260,574)
Net cash (used in) provided by financing activities	(255,873)	108,214	520,610
Cash acquired from the BRE merger	0	0	140,353
Cash acquired from consolidation of co-investment	0	4,005	0
Net increase in cash and cash equivalents	35,238	4,073	7,119
Cash and cash equivalents at beginning of year	29,683	25,610	18,491
Cash and cash equivalents at end of year	64,921	29,683	25,610
Supplemental disclosure of cash flow information:
Cash paid for interest, net of capitalized interest	203,743	181,106	130,691
Interest capitalized	12,486	15,571	22,510
Supplemental disclosure of noncash investing and financing activities:
Issuance of Operating Partnership units for contributed properties	0	0	1,419,816
Retirement of Operating Partnership units	0	0	(1,419,816)
Transfers between real estate under development to rental properties, net	104,159	308,704	10,203
Transfer from real estate under development to co-investments	9,919	6,234	83,574
Reclassifications (from) to redeemable noncontrolling interest to or from additional paid in capital and noncontrolling interest	(768)	22,387	18,766
Debt assumed in connection with acquisition (excluding BRE merger)	48,832	114,435	72,568
Debt deconsolidated in connection with BEX II transaction	20,195	0	0
Essex Portfolio, L.P. [Member]
Cash flows from operating activities:
Net income	438,410	248,239	134,438
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	441,682	453,423	360,592
Amortization of discount on marketable securities and other investments	(14,211)	(12,389)	(9,325)
Amortization of (premium) discount and financing costs, net	(15,234)	(19,361)	(14,672)
Gain on sale of marketable securities and other investments	(5,719)	(598)	(886)
Company's share of gain on the sales of co-investments	(13,046)	0	(6,558)
Earnings from co-investments	(35,652)	(21,861)	(33,335)
Operating distributions from co-investments	60,472	46,608	49,486
Gain on the sales of real estate and land	(154,561)	(47,333)	(46,039)
Equity-based compensation	10,899	6,061	8,740
Loss on early retirement of debt, net	606	6,114	268
Gain on remeasurement of co-investments	0	(34,014)	0
Noncash merger and integration expenses	0	0	9,025
Changes in operating assets and liabilities:
Prepaid expenses, receivables and other assets	(2,328)	267	15,828
Accounts payable and accrued liabilities	1,701	(9,633)	24,233
Other liabilities	(496)	1,887	1,517
Net cash provided by operating activities	712,523	617,410	493,312
Additions to real estate:
Acquisitions of real estate and acquisition related capital expenditures	(315,632)	(515,726)	(387,547)
Redevelopment	(83,927)	(99,346)	(81,429)
Development acquisitions of and additions to real estate under development	(76,455)	(157,900)	(152,766)
Capital expenditures on rental properties	(60,013)	(57,277)	(78,864)
Acquisition of membership interest in co-investments	0	(115,724)	0
Collections of notes and other receivables	4,070	0	76,585
Investments in notes receivable	(24,070)	0	0
Proceeds from insurance for property losses	5,543	16,811	35,547
BRE merger consideration paid	0	0	(555,826)
Proceeds from dispositions of real estate	239,289	319,008	141,189
Contributions to co-investments	(183,989)	(127,879)	(246,006)
Changes in restricted cash and refundable deposits	(14,138)	(14,068)	(36,582)
Purchases of marketable securities	(18,779)	(14,300)	(20,516)
Sales and maturities of marketable securities and other investments	30,458	8,907	8,753
Non-operating distributions from co-investments	76,231	31,938	150,306
Net cash used in investing activities	(421,412)	(725,556)	(1,147,156)
Cash flows from financing activities:
Borrowings under debt agreements	1,265,388	1,345,855	2,093,406
Repayment of debt	(1,018,126)	(1,197,351)	(1,814,020)
Repayment of cumulative redeemable preferred stock	(73,750)	0	0
Additions to deferred charges	(7,926)	(8,034)	(17,402)
Net proceeds from issuance of common stock	(384)	332,137	531,379
Net proceeds from stock options exercised	18,949	26,540	11,039
Distributions to noncontrolling interest	(6,960)	(7,615)	(4,841)
Redemption of noncontrolling interest	(2,511)	(2,621)	(802)
Common and preferred stock dividends paid	(429,508)	(380,697)	(278,149)
Net cash (used in) provided by financing activities	(255,873)	108,214	520,610
Cash acquired from the BRE merger	0	0	140,353
Cash acquired from consolidation of co-investment	0	4,005	0
Net increase in cash and cash equivalents	35,238	4,073	7,119
Cash and cash equivalents at beginning of year	29,683	25,610	18,491
Cash and cash equivalents at end of year	64,921	29,683	25,610
Supplemental disclosure of cash flow information:
Cash paid for interest, net of capitalized interest	203,743	181,106	130,691
Interest capitalized	12,486	15,571	22,510
Supplemental disclosure of noncash investing and financing activities:
Issuance of Operating Partnership units for contributed properties	0	0	1,419,816
Retirement of Operating Partnership units	0	0	(1,419,816)
Transfers between real estate under development to rental properties, net	104,159	308,704	10,203
Transfer from real estate under development to co-investments	9,919	6,234	83,574
Reclassifications (from) to redeemable noncontrolling interest to or from additional paid in capital and noncontrolling interest	(768)	22,387	18,766
Debt assumed in connection with acquisition (excluding BRE merger)	48,832	114,435	72,568
Debt deconsolidated in connection with BEX II transaction	$ 20,195	$ 0	$ 0