CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME OF ERP OPERATING LIMITED PARTNERSHIP (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income	$ 658,683us-gaap_ProfitLoss	$ 1,905,353us-gaap_ProfitLoss	$ 881,204us-gaap_ProfitLoss
Other comprehensive (loss) income - derivative instruments:
Unrealized holding (losses) gains arising during the year	(33,306)	18,771	(11,772)
Losses reclassified into earnings from other comprehensive income	(16,868)	(20,141)	(14,678)
Other comprehensive income (loss) - other instruments:
Unrealized holding gains arising during the year	0	583	664
(Gains) realized during the year	0us-gaap_GainLossOnSaleOfSecuritiesNet	(2,122)us-gaap_GainLossOnSaleOfSecuritiesNet	0us-gaap_GainLossOnSaleOfSecuritiesNet
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the year	(552)	613	0
Other comprehensive (loss) income	(16,990)	37,986	3,570
Comprehensive income	641,693	1,943,339	884,774
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	26,728	76,204	39,624
Comprehensive income attributable to controlling interests	614,965us-gaap_ComprehensiveIncomeNetOfTax	1,867,135us-gaap_ComprehensiveIncomeNetOfTax	845,150us-gaap_ComprehensiveIncomeNetOfTax
Partnership Interest [Member]
Net income	658,683	1,905,353	881,204
Other comprehensive (loss) income - derivative instruments:
Unrealized holding (losses) gains arising during the year	(33,306)	18,771	(11,772)
Losses reclassified into earnings from other comprehensive income	(16,868)	(20,141)	(14,678)
Other comprehensive income (loss) - other instruments:
Unrealized holding gains arising during the year	0	583	664
(Gains) realized during the year	0	(2,122)	0
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the year	(552)	613	0
Other comprehensive (loss) income	(16,990)	37,986	3,570
Comprehensive income	641,693	1,943,339	884,774
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	2,544	(538)	844
Comprehensive income attributable to controlling interests	$ 639,149	$ 1,943,877	$ 883,930

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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