CONSOLIDATED STATEMENTS OF OPERATIONS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
REVENUES
Rental income	$ 662,302	$ 632,831
Fee and asset management	$ 192	$ 185
Type of Revenue [Extensible List]	us-gaap:ManagementServiceMember	us-gaap:ManagementServiceMember
Total revenues	$ 662,494	$ 633,016
EXPENSES
Property and maintenance	115,070	108,202
Real estate taxes and insurance	91,442	91,914
Property management	26,396	23,444
General and administrative	15,381	16,278
Depreciation	204,215	196,309
Total expenses	452,504	436,147
Net gain (loss) on sales of real estate properties	(21)	142,213
Operating income	209,969	339,082
Interest and other income	581	5,880
Other expenses	(3,275)	(3,441)
Interest:
Expense incurred, net	(94,938)	(116,104)
Amortization of deferred financing costs	(2,136)	(3,679)
Income before income and other taxes, income (loss) from investments in unconsolidated entities and net gain (loss) on sales of land parcels	110,201	221,738
Income and other tax (expense) benefit	(238)	(213)
Income (loss) from investments in unconsolidated entities	(707)	(977)
Net gain (loss) on sales of land parcels	1
Net income	109,257	220,548
Partially Owned Properties	(799)	(680)
Net income attributable to controlling interests	$ 104,539	$ 211,809
Earnings per Unit – basic:
Net income available to Units	$ 0.28	$ 0.57
Earnings per Unit – diluted:
Net income available to Units	$ 0.28	$ 0.57
Weighted average Units outstanding	385,184	383,018
ERPOP [Member]
REVENUES
Rental income	$ 662,302	$ 632,831
Fee and asset management	$ 192	$ 185
Type of Revenue [Extensible List]	us-gaap:ManagementServiceMember	us-gaap:ManagementServiceMember
Total revenues	$ 662,494	$ 633,016
EXPENSES
Property and maintenance	115,070	108,202
Real estate taxes and insurance	91,442	91,914
Property management	26,396	23,444
General and administrative	15,381	16,278
Depreciation	204,215	196,309
Total expenses	452,504	436,147
Net gain (loss) on sales of real estate properties	(21)	142,213
Operating income	209,969	339,082
Interest and other income	581	5,880
Other expenses	(3,275)	(3,441)
Interest:
Expense incurred, net	(94,938)	(116,104)
Amortization of deferred financing costs	(2,136)	(3,679)
Income before income and other taxes, income (loss) from investments in unconsolidated entities and net gain (loss) on sales of land parcels	110,201	221,738
Income and other tax (expense) benefit	(238)	(213)
Income (loss) from investments in unconsolidated entities	(707)	(977)
Net gain (loss) on sales of land parcels	1
Net income	109,257	220,548
Partially Owned Properties	(799)	(680)
Net income attributable to controlling interests	108,458	219,868
ALLOCATION OF NET INCOME:
Preference Units	773	773
General Partner	103,766	211,036
Limited Partners	3,919	8,059
Net income available to Units	$ 107,685	$ 219,095
Earnings per Unit – basic:
Net income available to Units	$ 0.28	$ 0.57
Weighted average Units outstanding	382,477	380,663
Earnings per Unit – diluted:
Net income available to Units	$ 0.28	$ 0.57
Weighted average Units outstanding	385,184	383,018