CONSOLIDATED BALANCE SHEETS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Investment in real estate
Land	$ 6,264,787,000	$ 4,554,912,000
Depreciable property	19,568,973,000	15,711,944,000
Projects under development	585,749,000	387,750,000
Land held for development	569,398,000	353,823,000
Real Estate Investment Property, at Cost	26,988,907,000	21,008,429,000
Real Estate Investment Property, Accumulated Depreciation	(4,547,327,000)	(4,912,221,000)
Investment in real estate, net	22,441,580,000	16,096,208,000
Cash and cash equivalents	152,564,000	612,590,000
Investments in unconsolidated entities	188,582,000	17,877,000
Deposits - restricted	197,267,000	250,442,000
Escrow deposits - mortgage	41,357,000	9,129,000
Deferred financing costs, net	71,013,000	44,382,000
Other assets	390,020,000	170,372,000
Total assets	23,482,383,000	17,201,000,000
Liabilities:
Mortgage notes payable	6,247,612,000	3,898,369,000
Notes, net	5,475,954,000	4,630,875,000
Lines of credit	0	0
Accounts payable and accrued expenses	84,603,000	38,372,000
Accrued interest payable	86,083,000	76,223,000
Other liabilities	318,622,000	304,518,000
Security deposits	71,857,000	66,988,000
Distributions payable	150,846,000	260,176,000
Total liabilities	12,435,577,000	9,275,521,000
Commitments and contingencies
Partners’ Capital:
Accumulated other comprehensive (loss)	(166,844,000)	(193,148,000)
Noncontrolling Interests - Partially Owned Properties	107,493,000	77,688,000
Total liabilities and equity	23,482,383,000	17,201,000,000
OPERATING PARTNERSHIP
Investment in real estate
Land	6,264,787,000	4,554,912,000
Depreciable property	19,568,973,000	15,711,944,000
Projects under development	585,749,000	387,750,000
Land held for development	569,398,000	353,823,000
Real Estate Investment Property, at Cost	26,988,907,000	21,008,429,000
Real Estate Investment Property, Accumulated Depreciation	(4,547,327,000)	(4,912,221,000)
Investment in real estate, net	22,441,580,000	16,096,208,000
Cash and cash equivalents	152,564,000	612,590,000
Investments in unconsolidated entities	188,582,000	17,877,000
Deposits - restricted	197,267,000	250,442,000
Escrow deposits - mortgage	41,357,000	9,129,000
Deferred financing costs, net	71,013,000	44,382,000
Other assets	390,020,000	170,372,000
Total assets	23,482,383,000	17,201,000,000
Liabilities:
Mortgage notes payable	6,247,612,000	3,898,369,000
Notes, net	5,475,954,000	4,630,875,000
Lines of credit	0	0
Accounts payable and accrued expenses	84,603,000	38,372,000
Accrued interest payable	86,083,000	76,223,000
Other liabilities	318,622,000	304,518,000
Security deposits	71,857,000	66,988,000
Distributions payable	150,846,000	260,176,000
Total liabilities	12,435,577,000	9,275,521,000
Commitments and contingencies
Redeemable Limited Partners	407,890,000	398,372,000
Partners’ Capital:
Preference Units	50,000,000	50,000,000
General Partner	10,439,228,000	7,432,961,000
Limited Partners	209,039,000	159,606,000
Accumulated other comprehensive (loss)	(166,844,000)	(193,148,000)
Total partners’ capital	10,531,423,000	7,449,419,000
Noncontrolling Interests - Partially Owned Properties	107,493,000	77,688,000
Total capital	10,638,916,000	7,527,107,000
Total liabilities and equity	$ 23,482,383,000	$ 17,201,000,000