CONSOLIDATED STATEMENTS OF CASH FLOWS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 641,641	$ 835,736
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	667,896	616,032
Amortization of deferred financing costs	6,421	6,172
Amortization of above/below market lease intangibles		(154)
Amortization of discounts and premiums on debt	4,123	3,934
Amortization of deferred settlements on derivative instruments	9,978	6,991
Amortization of right-of-use assets	9,123	10,286
Write-off of pursuit costs	3,296	3,557
(Income) loss from investments in unconsolidated entities	3,456	3,028
Distributions from unconsolidated entities – return on capital	251
Net (gain) loss on sales of real estate properties	(304,346)	(587,623)
Net (gain) loss on sales of land parcels		(5)
Realized (gain) loss on sale of investment securities	(2,061)	(23,432)
Compensation paid with Company Common Shares	24,559	21,919
Changes in assets and liabilities:
(Increase) decrease in other assets	20,734	16,269
Increase (decrease) in accounts payable and accrued expenses	76,274	69,170
Increase (decrease) in accrued interest payable	(19,858)	(9,119)
Increase (decrease) in lease liabilities	(1,166)	(4,112)
Increase (decrease) in other liabilities	(23,199)	5,427
Increase (decrease) in security deposits	3,106	4,137
Net cash provided by operating activities	1,120,228	978,213
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(113,046)	(1,022,275)
Investment in real estate – development/other	(81,889)	(172,850)
Capital expenditures to real estate	(141,707)	(107,706)
Non-real estate capital additions	(2,232)	(1,251)
Interest capitalized for real estate and unconsolidated entities under development	(4,181)	(12,365)
Proceeds from disposition of real estate, net	720,302	1,014,328
Investments in unconsolidated entities - acquisitions	(49,330)	(21,787)
Investments in unconsolidated entities – development/other	(87,129)	(9,294)
Distributions from unconsolidated entities – return of capital	9	4
Purchase of investment securities and other investments	(1,045)	(167,791)
Proceeds from sale of investment securities	3,584	191,398
Net cash provided by (used for) investing activities	243,336	(309,589)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(373)	(6,447)
Mortgage notes payable, net:
Proceeds	37,429	51,298
Lump sum payoffs	(260,874)	(59,880)
Scheduled principal repayments	(3,186)	(5,570)
Notes, net:
Proceeds		497,470
Lump sum payoffs	(500,000)
Line of credit and commercial paper:
Commercial paper proceeds	5,140,685	4,305,170
Commercial paper repayments	(5,266,158)	(4,690,000)
Finance ground lease principal payments	(1,845)	(349)
Proceeds from Employee Share Purchase Plan (ESPP)	3,280	3,455
Proceeds from exercise of EQR options	21,021	68,807
Payment of offering costs	(739)	(267)
Other financing activities, net	(31)	(31)
Acquisition of Noncontrolling Interests – Partially Owned Properties	(32,178)
Contributions – Noncontrolling Interests – Partially Owned Properties	603
Contributions – Limited Partners	1
Distributions:
OP Units – General Partner	(696,679)	(674,531)
Preference Units	(2,318)	(2,318)
OP Units – Limited Partners	(22,735)	(23,949)
Noncontrolling Interests – Partially Owned Properties	(18,236)	(4,461)
Net cash provided by (used for) financing activities	(1,602,333)	(541,603)
Net increase (decrease) in cash and cash equivalents and restricted deposits	(238,769)	127,021
Cash and cash equivalents and restricted deposits, beginning of period	360,236	99,728
Cash and cash equivalents and restricted deposits, end of period	121,467	226,749
Cash and cash equivalents	44,788	39,707
Restricted deposits	76,679	187,042
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	221,218	199,799
Net cash paid (received) for income and other taxes	728	1,040
Amortization of deferred financing costs:
Investment in real estate, net	(380)	(227)
Other assets	1,754	1,754
Mortgage notes payable, net	1,620	1,702
Notes, net	3,427	2,943
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	1,865	2,069
Notes, net	2,258	1,865
Amortization of deferred settlements on derivative instruments:
Other liabilities	(9)	(9)
Accumulated other comprehensive income	9,987	7,000
Write-off of pursuit costs:
Investment in real estate, net	948	3,000
Investments in unconsolidated entities	2,197
Other assets	151	533
Accounts payable and accrued expenses		24
(Income) loss from investments in unconsolidated entities:
Investments in unconsolidated entities	2,517	2,062
Other liabilities	939	966
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(23,413)
Accumulated other comprehensive income	23,413
Interest capitalized for real estate and unconsolidated entities under development:
Investment in real estate, net	(1,312)	(12,260)
Investments in unconsolidated entities	2,869	105
Investments in unconsolidated entities - development/other:
Investment in real estate, net		967
Investments in unconsolidated entities	(85,839)	(8,251)
Other liabilities	(1,290)	(2,010)
Debt financing costs:
Other assets	(45)	228
Mortgage notes payable, net	(228)	(2,344)
Notes, net	(100)	(4,331)
Right-of-use assets and lease liabilities initial measurement and reclassifications:
Right-of-use assets	(224)	11,308
Lease liabilities	224	(11,308)
Non-cash share distribution and other transfers from unconsolidated entities:
Investments in unconsolidated entities	4,201	1,430
Other assets	(4,201)	(1,430)
ERPOP [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	641,641	835,736
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	667,896	616,032
Amortization of deferred financing costs	6,421	6,172
Amortization of above/below market lease intangibles		(154)
Amortization of discounts and premiums on debt	4,123	3,934
Amortization of deferred settlements on derivative instruments	9,978	6,991
Amortization of right-of-use assets	9,123	10,286
Write-off of pursuit costs	3,296	3,557
(Income) loss from investments in unconsolidated entities	3,456	3,028
Distributions from unconsolidated entities – return on capital	251
Net (gain) loss on sales of real estate properties	(304,346)	(587,623)
Net (gain) loss on sales of land parcels		(5)
Realized (gain) loss on sale of investment securities	(2,061)	(23,432)
Compensation paid with Company Common Shares	24,559	21,919
Changes in assets and liabilities:
(Increase) decrease in other assets	20,734	16,269
Increase (decrease) in accounts payable and accrued expenses	76,274	69,170
Increase (decrease) in accrued interest payable	(19,858)	(9,119)
Increase (decrease) in lease liabilities	(1,166)	(4,112)
Increase (decrease) in other liabilities	(23,199)	5,427
Increase (decrease) in security deposits	3,106	4,137
Net cash provided by operating activities	1,120,228	978,213
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(113,046)	(1,022,275)
Investment in real estate – development/other	(81,889)	(172,850)
Capital expenditures to real estate	(141,707)	(107,706)
Non-real estate capital additions	(2,232)	(1,251)
Interest capitalized for real estate and unconsolidated entities under development	(4,181)	(12,365)
Proceeds from disposition of real estate, net	720,302	1,014,328
Investments in unconsolidated entities - acquisitions	(49,330)	(21,787)
Investments in unconsolidated entities – development/other	(87,129)	(9,294)
Distributions from unconsolidated entities – return of capital	9	4
Purchase of investment securities and other investments	(1,045)	(167,791)
Proceeds from sale of investment securities	3,584	191,398
Net cash provided by (used for) investing activities	243,336	(309,589)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(373)	(6,447)
Mortgage notes payable, net:
Proceeds	37,429	51,298
Lump sum payoffs	(260,874)	(59,880)
Scheduled principal repayments	(3,186)	(5,570)
Notes, net:
Proceeds		497,470
Lump sum payoffs	(500,000)
Line of credit and commercial paper:
Commercial paper proceeds	5,140,685	4,305,170
Commercial paper repayments	(5,266,158)	(4,690,000)
Finance ground lease principal payments	(1,845)	(349)
Proceeds from Employee Share Purchase Plan (ESPP)	3,280	3,455
Proceeds from exercise of EQR options	21,021	68,807
Payment of offering costs	(739)	(267)
Other financing activities, net	(31)	(31)
Acquisition of Noncontrolling Interests – Partially Owned Properties	(32,178)
Contributions – Noncontrolling Interests – Partially Owned Properties	603
Contributions – Limited Partners	1
Distributions:
OP Units – General Partner	(696,679)	(674,531)
Preference Units	(2,318)	(2,318)
OP Units – Limited Partners	(22,735)	(23,949)
Noncontrolling Interests – Partially Owned Properties	(18,236)	(4,461)
Net cash provided by (used for) financing activities	(1,602,333)	(541,603)
Net increase (decrease) in cash and cash equivalents and restricted deposits	(238,769)	127,021
Cash and cash equivalents and restricted deposits, beginning of period	360,236	99,728
Cash and cash equivalents and restricted deposits, end of period	121,467	226,749
Cash and cash equivalents	44,788	39,707
Restricted deposits	76,679	187,042
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	221,218	199,799
Net cash paid (received) for income and other taxes	728	1,040
Amortization of deferred financing costs:
Investment in real estate, net	(380)	(227)
Other assets	1,754	1,754
Mortgage notes payable, net	1,620	1,702
Notes, net	3,427	2,943
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	1,865	2,069
Notes, net	2,258	1,865
Amortization of deferred settlements on derivative instruments:
Other liabilities	(9)	(9)
Accumulated other comprehensive income	9,987	7,000
Write-off of pursuit costs:
Investment in real estate, net	948	3,000
Investments in unconsolidated entities	2,197
Other assets	151	533
Accounts payable and accrued expenses		24
(Income) loss from investments in unconsolidated entities:
Investments in unconsolidated entities	2,517	2,062
Other liabilities	939	966
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(23,413)
Accumulated other comprehensive income	23,413
Interest capitalized for real estate and unconsolidated entities under development:
Investment in real estate, net	(1,312)	(12,260)
Investments in unconsolidated entities	(2,869)	(105)
Investments in unconsolidated entities - development/other:
Investment in real estate, net		967
Investments in unconsolidated entities	(85,839)	(8,251)
Other liabilities	(1,290)	(2,010)
Debt financing costs:
Other assets	(45)	228
Mortgage notes payable, net	(228)	(2,344)
Notes, net	(100)	(4,331)
Right-of-use assets and lease liabilities initial measurement and reclassifications:
Right-of-use assets	(224)	11,308
Lease liabilities	224	(11,308)
Non-cash share distribution and other transfers from unconsolidated entities:
Investments in unconsolidated entities	4,201	1,430
Other assets	$ (4,201)	$ (1,430)