CONSOLIDATED STATEMENTS OF OPERATIONS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
REVENUES
Rental income	$ 664,606,000	$ 630,725,000
Fee and asset management	1,765,000	2,717,000
Total revenues	666,371,000	633,442,000
EXPENSES
Property and maintenance	124,560,000	125,566,000
Real estate taxes and insurance	86,432,000	82,094,000
Property management	21,444,000	22,118,000
Fee and asset management	1,321,000	1,662,000
Depreciation	194,521,000	185,167,000
General and administrative	19,922,000	17,576,000
Total expenses	448,200,000	434,183,000
Operating Income	218,171,000	199,259,000
Interest and other income	120,000	605,000
Other expenses	70,000	(664,000)
Interest:
Expense incurred, net	(108,622,000)	(113,049,000)
Amortization of deferred financing costs	(2,589,000)	(2,792,000)
Income before income and other taxes, income (loss) from investments in unconsolidated entities, net gain (loss) on sales of real estate properties and land parcels and discontinued operations	107,150,000	83,359,000
Income and other tax (expense) benefit	(43,000)	(240,000)
Income (loss) from investments in unconsolidated entities	2,963,000	(1,409,000)
Net gain on sales of real estate properties	79,951,000	0
Net (loss) on sales of land parcels	(1,000)	(30,000)
Income from continuing operations	190,020,000	81,680,000
Discontinued operations, net	204,000	1,052,000
Net income	190,224,000	82,732,000
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(643,000)	(504,000)
Net income attributable to controlling interests	182,522,000	79,135,000
ALLOCATION OF NET INCOME:
Premium on redemption of Preferred Shares	(2,789,000)	0
Earnings per Unit - basic:
Income from continuing operations available to Units	$ 0.492	$ 0.214
Net income available to Units	$ 0.493	$ 0.217
Earnings per Unit - diluted:
Income from continuing operations available to Units	$ 0.488	$ 0.213
Net income available to Units	$ 0.489	$ 0.216
OPERATING PARTNERSHIP
REVENUES
Rental income	664,606,000	630,725,000
Fee and asset management	1,765,000	2,717,000
Total revenues	666,371,000	633,442,000
EXPENSES
Property and maintenance	124,560,000	125,566,000
Real estate taxes and insurance	86,432,000	82,094,000
Property management	21,444,000	22,118,000
Fee and asset management	1,321,000	1,662,000
Depreciation	194,521,000	185,167,000
General and administrative	19,922,000	17,576,000
Total expenses	448,200,000	434,183,000
Operating Income	218,171,000	199,259,000
Interest and other income	120,000	605,000
Other expenses	70,000	(664,000)
Interest:
Expense incurred, net	(108,622,000)	(113,049,000)
Amortization of deferred financing costs	(2,589,000)	(2,792,000)
Income before income and other taxes, income (loss) from investments in unconsolidated entities, net gain (loss) on sales of real estate properties and land parcels and discontinued operations	107,150,000	83,359,000
Income and other tax (expense) benefit	(43,000)	(240,000)
Income (loss) from investments in unconsolidated entities	2,963,000	(1,409,000)
Net gain on sales of real estate properties	79,951,000	0
Net (loss) on sales of land parcels	(1,000)	(30,000)
Income from continuing operations	190,020,000	81,680,000
Discontinued operations, net	204,000	1,052,000
Net income	190,224,000	82,732,000
Net (income) attributable to Noncontrolling Interests – Partially Owned Properties	(643,000)	(504,000)
Net income attributable to controlling interests	189,581,000	82,228,000
ALLOCATION OF NET INCOME:
Preference Units	891,000	1,036,000
Premium on redemption of Preferred Shares	2,789,000	0
General Partner	178,842,000	78,099,000
Limited Partners	7,059,000	3,093,000
Net income available to Units	$ 185,901,000	$ 81,192,000
Earnings per Unit - basic:
Income from continuing operations available to Units	$ 0.492	$ 0.214
Net income available to Units	$ 0.493	$ 0.217
Weighted average Units outstanding	376,696	374,201
Earnings per Unit - diluted:
Income from continuing operations available to Units	$ 0.488	$ 0.213
Net income available to Units	$ 0.489	$ 0.216
Weighted average Units outstanding	380,327	376,384
Distributions declared per Unit outstanding	$ 0.5525	$ 0.50