Condensed Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 366,932	$ 350,917	$ 1,084,790	$ 1,046,895
Expenses:
Property operating, excluding real estate taxes	63,181	59,100	181,241	174,461
Real estate taxes	39,290	38,675	114,993	112,423
Corporate-level property management expenses	8,255	7,761	24,620	23,313
Depreciation and amortization	120,809	120,852	360,842	359,287
General and administrative	11,345	10,601	38,731	36,539
Expensed acquisition and investment related costs	13	31	69	156
Total expenses	242,893	237,020	720,496	706,179
Gain on sale of real estate and land	0	0	0	22,244
Earnings from operations	124,039	113,897	364,294	362,960
Interest expense	(54,896)	(55,196)	(162,651)	(166,335)
Total return swap income	2,154	2,184	6,174	6,682
Interest and other income	8,685	8,437	29,293	21,241
Equity income from co-investments	21,700	16,788	54,935	64,611
Deferred tax expense on unrealized gain on unconsolidated co-investment	(1,457)	0	(1,457)	0
Gain on early retirement of debt, net	5,475	0	7,143	0
Gain on remeasurement of co-investment	0	0	31,535	0
Net income	105,700	86,110	329,266	289,159
Net income attributable to noncontrolling interest	(6,365)	(5,135)	(18,798)	(16,826)
Net income available to common stockholders	99,335	80,975	310,468	272,333
Comprehensive income	105,663	89,100	323,071	301,708
Comprehensive income attributable to noncontrolling interest	(6,364)	(5,235)	(18,589)	(17,243)
Comprehensive income attributable to controlling interest	$ 99,299	$ 83,865	$ 304,482	$ 284,465
Basic:
Net income available to common stockholders/unitholders (in dollars per share)	$ 1.51	$ 1.23	$ 4.72	$ 4.12
Weighted average number of shares/common units outstanding during the period (in shares)	65,850,524	66,052,108	65,757,914	66,047,990
Diluted:
Net income available to common stockholders/unitholders (in dollars per share)	$ 1.51	$ 1.22	$ 4.71	$ 4.12
Weighted average number of shares/common units outstanding during the period (in shares)	65,973,085	66,103,812	65,857,660	66,093,004
Rental and Other Property Revenues [Member]
Revenues:
Total revenues	$ 364,504	$ 348,610	$ 1,077,767	$ 1,040,083
Management and Other Fees From Affiliates Income [Member]
Revenues:
Total revenues	2,428	2,307	7,023	6,812
Essex Portfolio, L.P. [Member]
Revenues:
Total revenues	366,932	350,917	1,084,790	1,046,895
Expenses:
Property operating, excluding real estate taxes	63,181	59,100	181,241	174,461
Real estate taxes	39,290	38,675	114,993	112,423
Corporate-level property management expenses	8,255	7,761	24,620	23,313
Depreciation and amortization	120,809	120,852	360,842	359,287
General and administrative	11,345	10,601	38,731	36,539
Expensed acquisition and investment related costs	13	31	69	156
Total expenses	242,893	237,020	720,496	706,179
Gain on sale of real estate and land	0	0	0	22,244
Earnings from operations	124,039	113,897	364,294	362,960
Interest expense	(54,896)	(55,196)	(162,651)	(166,335)
Total return swap income	2,154	2,184	6,174	6,682
Interest and other income	8,685	8,437	29,293	21,241
Equity income from co-investments	21,700	16,788	54,935	64,611
Deferred tax expense on unrealized gain on unconsolidated co-investment	(1,457)	0	(1,457)	0
Gain on early retirement of debt, net	5,475	0	7,143	0
Gain on remeasurement of co-investment	0	0	31,535	0
Net income	105,700	86,110	329,266	289,159
Net income attributable to noncontrolling interest	(2,901)	(2,346)	(7,935)	(7,445)
Net income available to common stockholders	102,799	83,764	321,331	281,714
Comprehensive income	105,663	89,100	323,071	301,708
Comprehensive income attributable to noncontrolling interest	(2,901)	(2,346)	(7,935)	(7,445)
Comprehensive income attributable to controlling interest	$ 102,762	$ 86,754	$ 315,136	$ 294,263
Basic:
Net income available to common stockholders/unitholders (in dollars per share)	$ 1.51	$ 1.23	$ 4.72	$ 4.12
Weighted average number of shares/common units outstanding during the period (in shares)	68,148,913	68,325,091	68,058,802	68,321,153
Diluted:
Net income available to common stockholders/unitholders (in dollars per share)	$ 1.51	$ 1.23	$ 4.71	$ 4.12
Weighted average number of shares/common units outstanding during the period (in shares)	68,271,474	68,376,795	68,158,548	68,366,167
Essex Portfolio, L.P. [Member] | Rental and Other Property Revenues [Member]
Revenues:
Total revenues	$ 364,504	$ 348,610	$ 1,077,767	$ 1,040,083
Essex Portfolio, L.P. [Member] | Management and Other Fees From Affiliates Income [Member]
Revenues:
Total revenues	$ 2,428	$ 2,307	$ 7,023	$ 6,812