Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income	$ 163,731	$ 115,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	219,380	220,638
Amortization of discount on marketable securities and other investments	(7,457)	(5,777)
Amortization of (premium) discount and debt financing costs, net	(7,598)	(11,125)
Gain on sale of marketable securities	(1,843)	0
Company's share of gain on the sales of co-investments	(13,046)	0
Income from early redemption of preferred equity investments	0	(469)
Earnings from co-investments	(16,318)	(8,314)
Operating distributions from co-investments	23,985	14,804
Gain on the sale of real estate and land	(20,258)	(7,112)
Equity-based compensation	3,198	3,457
Gain on remeasurement of co-investments	0	(34,014)
Changes in operating assets and liabilities:
Prepaid expenses, receivables and other assets	(3,942)	(6,646)
Accounts payable and accrued liabilities	9,772	4,924
Other liabilities	749	1,387
Net cash provided by operating activities	350,353	287,048
Additions to real estate:
Acquisitions of real estate and acquisition related capital expenditures	(117,349)	(314,890)
Redevelopment	(43,200)	(41,796)
Development acquisitions of and additions to real estate under development	(37,150)	(122,377)
Capital expenditures on rental properties	(22,277)	(24,673)
Acquisition of membership interest in co-investments	0	(115,724)
Proceeds from insurance for property losses	1,211	11,735
Proceeds from dispositions of real estate	48,008	74,485
Contributions to co-investments	(96,698)	(97,512)
Changes in restricted cash and refundable deposits	56,932	49,808
Purchases of marketable securities	(16,352)	(7,250)
Sales and maturities of marketable securities	11,179	1,968
Non-operating distributions from co-investments	34,564	11,072
Net cash used in investing activities	(181,132)	(575,154)
Cash flows from financing activities:
Borrowings under debt agreements	768,610	923,431
Repayment of debt	(501,167)	(730,712)
Repayment of cumulative redeemable preferred stock	(73,750)	0
Additions to deferred charges	(4,962)	(4,456)
Net proceeds from issuance of common stock	(279)	272,664
Net proceeds from stock options exercised	11,760	18,346
Distributions to noncontrolling interest	(12,880)	(11,033)
Redemption of noncontrolling interest	(2,233)	(2,488)
Common and preferred stock dividends paid	(201,488)	(177,019)
Net cash (used in) provided by financing activities	(16,389)	288,733
Cash acquired in consolidation of co-investment	0	4,005
Net increase in cash and cash equivalents	152,832	4,632
Cash and cash equivalents at beginning of period	29,683	25,610
Cash and cash equivalents at end of period	182,515	30,242
Supplemental disclosure of cash flow information:
Cash paid for interest, net of $6.2 million and $8.3 million capitalized in 2016 and 2015, respectively	93,031	86,347
Cash paid for interest, capitalized	6,200	8,300
Supplemental disclosure of noncash investing and financing activities:
Transfers between real estate under development to rental properties, net	108,402	300,751
Transfer from real estate under development to co-investments	4,485	3,780
Reclassifications (from) to redeemable noncontrolling interest to or from additional paid in capital and noncontrolling interest	(921)	574
Debt assumed in connection with acquisition	48,832	114,435
Essex Portfolio, L.P. [Member]
Cash flows from operating activities:
Net income	163,731	115,295
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	219,380	220,638
Amortization of discount on marketable securities and other investments	(7,457)	(5,777)
Amortization of (premium) discount and debt financing costs, net	(7,598)	(11,125)
Gain on sale of marketable securities	(1,843)	0
Company's share of gain on the sales of co-investments	(13,046)
Income from early redemption of preferred equity investments	0	(469)
Earnings from co-investments	(16,318)	(8,314)
Operating distributions from co-investments	23,985	14,804
Gain on the sale of real estate and land	(20,258)	(7,112)
Equity-based compensation	3,198	3,457
Gain on remeasurement of co-investments	0	(34,014)
Changes in operating assets and liabilities:
Prepaid expenses, receivables and other assets	(3,942)	(6,646)
Accounts payable and accrued liabilities	9,772	4,924
Other liabilities	749	1,387
Net cash provided by operating activities	350,353	287,048
Additions to real estate:
Acquisitions of real estate and acquisition related capital expenditures	(117,349)	(314,890)
Redevelopment	(43,200)	(41,796)
Development acquisitions of and additions to real estate under development	(37,150)	(122,377)
Capital expenditures on rental properties	(22,277)	(24,673)
Acquisition of membership interest in co-investments	0	(115,724)
Proceeds from insurance for property losses	1,211	11,735
Proceeds from dispositions of real estate	48,008	74,485
Contributions to co-investments	(96,698)	(97,512)
Changes in restricted cash and refundable deposits	56,932	49,808
Purchases of marketable securities	(16,352)	(7,250)
Sales and maturities of marketable securities	11,179	1,968
Non-operating distributions from co-investments	34,564	11,072
Net cash used in investing activities	(181,132)	(575,154)
Cash flows from financing activities:
Borrowings under debt agreements	768,610	923,431
Repayment of debt	(501,167)	(730,712)
Repayment of cumulative redeemable preferred stock	(73,750)	0
Additions to deferred charges	(4,962)	(4,456)
Net proceeds from issuance of common stock	(279)	272,664
Net proceeds from stock options exercised	11,760	18,346
Distributions to noncontrolling interest	(3,379)	(4,884)
Redemption of noncontrolling interest	(2,233)	(2,488)
Common and preferred stock dividends paid	(210,989)	(183,168)
Net cash (used in) provided by financing activities	(16,389)	288,733
Cash acquired in consolidation of co-investment	0	4,005
Net increase in cash and cash equivalents	152,832	4,632
Cash and cash equivalents at beginning of period	29,683	25,610
Cash and cash equivalents at end of period	182,515	30,242
Supplemental disclosure of cash flow information:
Cash paid for interest, net of $6.2 million and $8.3 million capitalized in 2016 and 2015, respectively	93,031	86,347
Cash paid for interest, capitalized	6,200	8,300
Supplemental disclosure of noncash investing and financing activities:
Transfers between real estate under development to rental properties, net	108,402	300,751
Transfer from real estate under development to co-investments	4,485	3,780
Reclassifications (from) to redeemable noncontrolling interest to or from additional paid in capital and noncontrolling interest	(921)	574
Debt assumed in connection with acquisition	$ 48,832	$ 114,435