Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Rental and other property	$ 1,354,325	$ 1,285,723	$ 1,185,498
Management and other fees from affiliates	9,574	8,278	8,909
Total revenues	1,363,899	1,294,001	1,194,407
Expenses:
Property operating, excluding real estate taxes	259,232	249,765	234,953
Real estate taxes	146,310	139,162	128,555
Depreciation and amortization	468,881	441,682	453,423
General and administrative	41,385	40,751	40,090
Merger and integration expenses	0	0	3,798
Acquisition and investment related costs	1,569	1,841	2,414
Total expenses	917,377	873,201	863,233
Earnings from operations	446,522	420,800	331,174
Interest expense	(222,894)	(219,654)	(204,827)
Total return swap income	10,098	11,716	5,655
Interest and other income	24,604	27,305	19,143
Equity income from co-investments	86,445	48,698	21,861
Loss on early retirement of debt	(1,796)	(606)	(6,114)
Gain on sale of real estate and land	26,423	154,561	47,333
Deferred tax expense on gain on sale of real estate and land	0	(4,410)	0
Gain on remeasurement of co-investment	88,641	0	34,014
Net income	458,043	438,410	248,239
Net income attributable to noncontrolling interest	(24,984)	(23,431)	(16,119)
Net income attributable to controlling interest	433,059	414,979	232,120
Dividends to preferred stockholders	0	(1,314)	(5,255)
Excess of redemption value of preferred stock over the carrying value	0	(2,541)	0
Net income available to common stockholders	$ 433,059	$ 411,124	$ 226,865
Basic:
Net income available to common stockholders - basic (in dollars per share)	$ 6.58	$ 6.28	$ 3.50
Weighted average number of shares outstanding during the year	65,829,155	65,471,540	64,871,717
Diluted:
Net income available to common stockholders - diluted (in dollars per share)	$ 6.57	$ 6.27	$ 3.49
Weighted average number of shares outstanding during the year	65,898,255	65,587,816	65,061,685
Essex Portfolio, L.P. [Member]
Revenues:
Rental and other property	$ 1,354,325	$ 1,285,723	$ 1,185,498
Management and other fees from affiliates	9,574	8,278	8,909
Total revenues	1,363,899	1,294,001	1,194,407
Expenses:
Property operating, excluding real estate taxes	259,232	249,765	234,953
Real estate taxes	146,310	139,162	128,555
Depreciation and amortization	468,881	441,682	453,423
General and administrative	41,385	40,751	40,090
Merger and integration expenses	0	0	3,798
Acquisition and investment related costs	1,569	1,841	2,414
Total expenses	917,377	873,201	863,233
Earnings from operations	446,522	420,800	331,174
Interest expense	(222,894)	(219,654)	(204,827)
Total return swap income	10,098	11,716	5,655
Interest and other income	24,604	27,305	19,143
Equity income from co-investments	86,445	48,698	21,861
Loss on early retirement of debt	(1,796)	(606)	(6,114)
Gain on sale of real estate and land	26,423	154,561	47,333
Deferred tax expense on gain on sale of real estate and land	0	(4,410)	0
Gain on remeasurement of co-investment	88,641	0	34,014
Net income	458,043	438,410	248,239
Net income attributable to noncontrolling interest	(10,159)	(9,342)	(8,295)
Net income attributable to controlling interest	447,884	429,068	239,944
Dividends to preferred stockholders	0	(1,314)	(5,255)
Excess of redemption value of preferred stock over the carrying value	0	(2,541)	0
Net income available to common stockholders	$ 447,884	$ 425,213	$ 234,689
Basic:
Net income available to common stockholders - basic (in dollars per share)	$ 6.58	$ 6.28	$ 3.50
Weighted average number of shares outstanding during the year	68,081,730	67,695,640	67,054,184
Diluted:
Net income available to common stockholders - diluted (in dollars per share)	$ 6.57	$ 6.27	$ 3.49
Weighted average number of shares outstanding during the year	68,150,830	67,811,916	67,244,152