CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Comprehensive income:
Net income	$ 298,618	$ 117,720	$ 488,842	$ 200,452
Other comprehensive (loss) income – derivative instruments:
Unrealized holding (losses) gains arising during the period	11,676	(9,929)	(112)	(21,881)
Losses reclassified into earnings from other comprehensive income	4,573	4,206	8,911	8,335
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the period	(82)	1,627	(502)	1,718
Other comprehensive income (loss)	16,167	(4,096)	8,297	(11,828)
Comprehensive income	314,785	113,624	497,139	188,624
Comprehensive (income) attributable to Noncontrolling Interests – Partially Owned Properties	(12,817)	(4,873)	(20,219)	(8,175)
Comprehensive income attributable to controlling interests	301,968	108,751	476,920	180,449
OPERATING PARTNERSHIP
Comprehensive income:
Net income	298,618	117,720	488,842	200,452
Other comprehensive (loss) income – derivative instruments:
Unrealized holding (losses) gains arising during the period	11,676	(9,929)	(112)	(21,881)
Losses reclassified into earnings from other comprehensive income	4,573	4,206	8,911	8,335
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the period	(82)	1,627	(502)	1,718
Other comprehensive income (loss)	16,167	(4,096)	8,297	(11,828)
Comprehensive income	314,785	113,624	497,139	188,624
Comprehensive (income) attributable to Noncontrolling Interests – Partially Owned Properties	(844)	(588)	(1,487)	(1,092)
Comprehensive income attributable to controlling interests	$ 313,941	$ 113,036	$ 495,652	$ 187,532