XML 142 R122.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Schedule III - Real Estate and Accumulated Depreciation-Overall Summary (Details) | Dec. 31, 2017 USD ($) Property ApartmentUnit | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
--- | --- | --- | --- | ---
Overall summary of real estate and accumulated depreciation |  |  |  |
Investment in Real Estate, Gross | $ 26,026,896,000 | $ 25,386,425,000 | $ 28,542,697,000 | $ 27,675,383,000
Accumulated Depreciation | $ (6,040,378,000) | $ (5,360,389,000) | $ (6,084,616,000) | $ (5,432,805,000)
Investment in Real Estate - Wholly Owned Unencumbered [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 215 |  |  |
Units | ApartmentUnit | 55,954 |  |  |
Investment in Real Estate, Gross | $ 19,776,737,815 |  |  |
Accumulated Depreciation | (4,363,244,353) |  |  |
Investment in Real Estate, Net | 15,413,493,462 |  |  |
Encumbrances | $ 0 |  |  |
Investment in Real Estate - Wholly Owned Encumbered [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 71 |  |  |
Units | ApartmentUnit | 18,497 |  |  |
Investment in Real Estate, Gross | $ 5,600,381,309 |  |  |
Accumulated Depreciation | (1,440,591,113) |  |  |
Investment in Real Estate, Net | 4,159,790,196 |  |  |
Encumbrances | $ 3,316,375,422 |  |  |
Wholly Owned Properties |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 286 |  |  |
Units | ApartmentUnit | 74,451 |  |  |
Investment in Real Estate, Gross | $ 25,377,119,124 |  |  |
Accumulated Depreciation | (5,803,835,466) |  |  |
Investment in Real Estate, Net | 19,573,283,658 |  |  |
Encumbrances | $ 3,316,375,422 |  |  |
Investment in Real Estate - Partially Owned Unencumbered [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 9 |  |  |
Units | ApartmentUnit | 1,527 |  |  |
Investment in Real Estate, Gross | $ 289,986,862 |  |  |
Accumulated Depreciation | (108,651,639) |  |  |
Investment in Real Estate, Net | 181,335,223 |  |  |
Encumbrances | $ 0 |  |  |
Investment in Real Estate - Partially Owned Encumbered [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 8 |  |  |
Units | ApartmentUnit | 1,688 |  |  |
Investment in Real Estate, Gross | $ 359,790,405 |  |  |
Accumulated Depreciation | (127,891,086) |  |  |
Investment in Real Estate, Net | 231,899,319 |  |  |
Encumbrances | $ 302,346,576 |  |  |
NONCONTROLLING INTERESTS – PARTIALLY OWNED PROPERTIES |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 17 |  |  |
Units | ApartmentUnit | 3,215 |  |  |
Investment in Real Estate, Gross | $ 649,777,267 |  |  |
Accumulated Depreciation | (236,542,725) |  |  |
Investment in Real Estate, Net | 413,234,542 |  |  |
Encumbrances | $ 302,346,576 |  |  |
Unencumbered Properties [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 224 |  |  |
Units | ApartmentUnit | 57,481 |  |  |
Investment in Real Estate, Gross | $ 20,066,724,677 |  |  |
Accumulated Depreciation | (4,471,895,992) |  |  |
Investment in Real Estate, Net | 15,594,828,685 |  |  |
Encumbrances | $ 0 |  |  |
Encumbered Properties [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 79 |  |  |
Units | ApartmentUnit | 20,185 |  |  |
Investment in Real Estate, Gross | $ 5,960,171,714 |  |  |
Accumulated Depreciation | (1,568,482,199) |  |  |
Investment in Real Estate, Net | 4,391,689,515 |  |  |
Encumbrances | $ 3,618,721,998 |  |  |
Total Consolidated Investment in Real Estate [Member] |  |  |  |
Overall summary of real estate and accumulated depreciation |  |  |  |
Properties | Property | 303 |  |  |
Units | ApartmentUnit | 77,666 |  |  |
Investment in Real Estate, Gross | $ 26,026,896,391 |  |  |
Accumulated Depreciation | (6,040,378,191) |  |  |
Investment in Real Estate, Net | 19,986,518,200 |  |  |
Encumbrances | $ 3,618,721,998 |  |  |

X
- Definition Overall summary of real estate and accumulated depreciation. + References No definition available. + Details
Name: | eqr_OverallSummaryOfRealEstateAndAccumulatedDepreciationAbstract
Namespace Prefix: | eqr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total number of properties which the company directly or indirectly through investments in title holding entities owns all or a portion of. + References No definition available. + Details
Name: | eqr_RealEstateAndAccumulatedDepreciationProperties
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total number of units associated with rental properties which the company directly or indirectly through investments in title holding entities owns all or a portion of. + References No definition available. + Details
Name: | eqr_RealEstateAndAccumulatedDepreciationUnits
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of accumulated depreciation pertaining to real estate investments for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28.FN4) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 + Details
Name: | us-gaap_RealEstateAccumulatedDepreciation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of lien or mortgage outstanding on real estate investment properties for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 + Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationAmountOfEncumbrances
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, before accumulated depreciation, of real estate investments for entities with a substantial portion of business acquiring and holding investment real estate. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28.4) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 + Details
Name: | us-gaap_RealEstateGrossAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount after accumulated depreciation of real estate held for investment for entities with a substantial portion of business acquiring and holding investment real estate. + References No definition available. + Details
Name: | us-gaap_SECScheduleIIIRealEstateInvestmentPropertyNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_EqrWhollyOwnedUnencumberedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_EqrWhollyOwnedEncumberedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=us-gaap_WhollyOwnedPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_EqrPartiallyOwnedUnencumberedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_EqrPartiallyOwnedEncumberedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=us-gaap_PartiallyOwnedPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_UnencumberedPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_EncumberedPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=eqr_TotalConsolidatedInvestmentInRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |