CONSOLIDATED STATEMENTS OF CASH FLOWS OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 220,548	$ 149,941
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	196,309	178,968
Amortization of deferred financing costs	3,679	2,296
Amortization of above/below market lease intangibles	1,098	856
Amortization of discounts and premiums on debt	1,532	1,130
Amortization of deferred settlements on derivative instruments	4,788	4,580
Write-off of pursuit costs	931	715
(Income) loss from investments in unconsolidated entities	977	1,073
Distributions from unconsolidated entities – return on capital	615	648
Net (gain) loss on sales of real estate properties	(142,213)	(36,707)
Net (gain) loss on sales of land parcels		(19,193)
Net (gain) loss on debt extinguishment	22,110	11,698
Compensation paid with Company Common Shares	10,278	7,873
Changes in assets and liabilities:
(Increase) decrease in other assets	(15,396)	(11,059)
Increase (decrease) in accounts payable and accrued expenses	48,997	42,472
Increase (decrease) in accrued interest payable	11,718	13,437
Increase (decrease) in other liabilities	(4,692)	(45,324)
Increase (decrease) in security deposits	(261)	500
Net cash provided by operating activities	361,018	303,904
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(54,134)
Investment in real estate – development/other	(40,813)	(103,291)
Capital expenditures to real estate	(36,747)	(39,297)
Non-real estate capital additions	(1,191)	(289)
Interest capitalized for real estate under development	(1,688)	(8,238)
Proceeds from disposition of real estate, net	284,670	80,064
Investments in unconsolidated entities	(2,799)	(1,704)
Distributions from unconsolidated entities – return of capital		113
Net cash provided by (used for) investing activities	147,298	(72,642)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(4,345)
Mortgage notes payable, net:
Lump sum payoffs	(725,639)	(351,774)
Scheduled principal repayments	(1,720)	(1,964)
Notes, net:
Proceeds	497,010
Line of credit and commercial paper:
Line of credit proceeds	415,000
Line of credit repayments	(415,000)
Commercial paper proceeds	1,107,561	1,310,188
Commercial paper repayments	(1,173,000)	(1,015,500)
Proceeds from (payments on) settlement of derivative instruments	1,638
Proceeds from EQR’s Employee Share Purchase Plan (ESPP)	1,681	1,574
Proceeds from exercise of EQR options	1,600	3,142
Payment of offering costs	(26)	(21)
Contributions – Noncontrolling Interests – Partially Owned Properties	125	125
Contributions – Limited Partners	1
Distributions:
OP Units – General Partner	(185,484)	(184,302)
Preference Units	(773)	(1,545)
OP Units – Limited Partners	(6,666)	(7,218)
Noncontrolling Interests – Partially Owned Properties	(4,220)	(5,134)
Net cash provided by (used for) financing activities	(514,367)	(264,127)
Net increase (decrease) in cash and cash equivalents and restricted deposits	(6,051)	(32,865)
Cash and cash equivalents and restricted deposits, beginning of period	100,762	219,088
Cash and cash equivalents and restricted deposits, end of period	94,711	186,223
Cash and cash equivalents	44,453	42,139
Restricted deposits	50,258	144,084
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	96,404	86,668
Net cash paid for income and other taxes	462	468
Amortization of deferred financing costs:
Other assets	603	603
Mortgage notes payable, net	2,084	794
Notes, net	992	899
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	897	525
Notes, net	635	605
Amortization of deferred settlements on derivative instruments:
Other liabilities	(3)	(3)
Accumulated other comprehensive income	4,791	4,583
Write-off of pursuit costs:
Investment in real estate, net	931	685
Other assets		10
Accounts payable and accrued expenses		20
(Income) loss from investments in unconsolidated entities:
Investments in unconsolidated entities	627	701
Other liabilities	350	372
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(9,132)	1,106
Notes, net	(2,289)	(1,106)
Other liabilities	5,334
Accumulated other comprehensive income	6,087
Investments in unconsolidated entities:
Investments in unconsolidated entities	(2,079)	(804)
Other liabilities	(720)	(900)
Debt financing costs:
Notes, net	(4,345)
Proceeds from (payments on) settlement of derivative instruments:
Other assets	1,638
Mortgage Notes Payable, Net [Member]
Mortgage notes payable, net:
Net gain (loss) on debt extinguishment	(22,110)	(11,698)
ERPOP [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	220,548	149,941
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	196,309	178,968
Amortization of deferred financing costs	3,679	2,296
Amortization of above/below market lease intangibles	1,098	856
Amortization of discounts and premiums on debt	1,532	1,130
Amortization of deferred settlements on derivative instruments	4,788	4,580
Write-off of pursuit costs	931	715
(Income) loss from investments in unconsolidated entities	977	1,073
Distributions from unconsolidated entities – return on capital	615	648
Net (gain) loss on sales of real estate properties	(142,213)	(36,707)
Net (gain) loss on sales of land parcels		(19,193)
Net (gain) loss on debt extinguishment	22,110	11,698
Compensation paid with Company Common Shares	10,278	7,873
Changes in assets and liabilities:
(Increase) decrease in other assets	(15,396)	(11,059)
Increase (decrease) in accounts payable and accrued expenses	48,997	42,472
Increase (decrease) in accrued interest payable	11,718	13,437
Increase (decrease) in other liabilities	(4,692)	(45,324)
Increase (decrease) in security deposits	(261)	500
Net cash provided by operating activities	361,018	303,904
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in real estate – acquisitions	(54,134)
Investment in real estate – development/other	(40,813)	(103,291)
Capital expenditures to real estate	(36,747)	(39,297)
Non-real estate capital additions	(1,191)	(289)
Interest capitalized for real estate under development	(1,688)	(8,238)
Proceeds from disposition of real estate, net	284,670	80,064
Investments in unconsolidated entities	(2,799)	(1,704)
Distributions from unconsolidated entities – return of capital		113
Net cash provided by (used for) investing activities	147,298	(72,642)
CASH FLOWS FROM FINANCING ACTIVITIES:
Debt financing costs	(4,345)
Mortgage notes payable, net:
Lump sum payoffs	(725,639)	(351,774)
Scheduled principal repayments	(1,720)	(1,964)
Notes, net:
Proceeds	497,010
Line of credit and commercial paper:
Line of credit proceeds	415,000
Line of credit repayments	(415,000)
Commercial paper proceeds	1,107,561	1,310,188
Commercial paper repayments	(1,173,000)	(1,015,500)
Proceeds from (payments on) settlement of derivative instruments	1,638
Proceeds from EQR’s Employee Share Purchase Plan (ESPP)	1,681	1,574
Proceeds from exercise of EQR options	1,600	3,142
Payment of offering costs	(26)	(21)
Contributions – Noncontrolling Interests – Partially Owned Properties	125	125
Contributions – Limited Partners	1
Distributions:
OP Units – General Partner	(185,484)	(184,302)
Preference Units	(773)	(1,545)
OP Units – Limited Partners	(6,666)	(7,218)
Noncontrolling Interests – Partially Owned Properties	(4,220)	(5,134)
Net cash provided by (used for) financing activities	(514,367)	(264,127)
Net increase (decrease) in cash and cash equivalents and restricted deposits	(6,051)	(32,865)
Cash and cash equivalents and restricted deposits, beginning of period	100,762	219,088
Cash and cash equivalents and restricted deposits, end of period	94,711	186,223
Cash and cash equivalents	44,453	42,139
Restricted deposits	50,258	144,084
SUPPLEMENTAL INFORMATION:
Cash paid for interest, net of amounts capitalized	96,404	86,668
Net cash paid for income and other taxes	462	468
Amortization of deferred financing costs:
Other assets	603	603
Mortgage notes payable, net	2,084	794
Notes, net	992	899
Amortization of discounts and premiums on debt:
Mortgage notes payable, net	897	525
Notes, net	635	605
Amortization of deferred settlements on derivative instruments:
Other liabilities	(3)	(3)
Accumulated other comprehensive income	4,791	4,583
Write-off of pursuit costs:
Investment in real estate, net	931	685
Other assets		10
Accounts payable and accrued expenses		20
(Income) loss from investments in unconsolidated entities:
Investments in unconsolidated entities	627	701
Other liabilities	350	372
Realized/unrealized (gain) loss on derivative instruments:
Other assets	(9,132)	1,106
Notes, net	(2,289)	(1,106)
Other liabilities	5,334
Accumulated other comprehensive income	6,087
Investments in unconsolidated entities:
Investments in unconsolidated entities	(2,079)	(804)
Other liabilities	(720)	(900)
Debt financing costs:
Notes, net	(4,345)
Proceeds from (payments on) settlement of derivative instruments:
Other assets	1,638
ERPOP [Member] | Mortgage Notes Payable, Net [Member]
Mortgage notes payable, net:
Net gain (loss) on debt extinguishment	$ (22,110)	$ (11,698)