Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income	$ 134,438us-gaap_ProfitLoss	$ 172,055us-gaap_ProfitLoss	$ 139,590us-gaap_ProfitLoss
Other comprehensive income (loss):
Changes in fair value of cash flow hedges and reclassification to interest expense	4,168	12,614	3,402
Changes in fair value of marketable securities	6,302	(1,556)	1,411
Reversal of unrealized gains upon the sale of marketable securities	(886)	(1,767)	(1,082)
Total other comprehensive income	9,584	9,291	3,731
Comprehensive income	144,022	181,346	143,321
Comprehensive income attributable to noncontrolling interest	(12,852)	(16,274)	(14,527)
Comprehensive income attributable to controlling interest	131,170us-gaap_ComprehensiveIncomeNetOfTax	165,072us-gaap_ComprehensiveIncomeNetOfTax	128,794us-gaap_ComprehensiveIncomeNetOfTax
Essex Portfolio, L.P. [Member]
Net income	134,438	172,055	139,590
Other comprehensive income (loss):
Changes in fair value of cash flow hedges and reclassification to interest expense	4,168	12,614	3,402
Changes in fair value of marketable securities	6,302	(1,556)	1,411
Reversal of unrealized gains upon the sale of marketable securities	(886)	(1,767)	(1,082)
Total other comprehensive income	9,584	9,291	3,731
Comprehensive income	144,022	181,346	143,321
Comprehensive income attributable to noncontrolling interest	(7,421)	(6,834)	(6,347)
Comprehensive income attributable to controlling interest	$ 136,601	$ 174,512	$ 136,974

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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