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Business - Additional Information (Details) | Mar. 31, 2018 State Property ApartmentUnit | Feb. 01, 2018 ApartmentUnit
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Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |  |
Number of states in which entity operates | State | 10 |
Properties | Property | 303 |
Apartment units | 78,399 |
Master-Leased Properties – Consolidated |  |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |  |
Properties | Property | 2 |
Apartment units | 759 |
Master-Leased Properties – Consolidated | Boston |  |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |  |
Number of self managed apartments |  | 94
ERPOP [Member] |  |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |  |
Noncontrolling interest, ownership percentage by parent | 96.30% |

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- Definition Number of self managed apartments. + References No definition available. + Details
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- Definition Organization consolidation and presentation of financial statements disclosure. + References No definition available. + Details
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- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
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- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
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- Definition The number of states the entity operates in as of the balance sheet date. + References No definition available. + Details
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- Definition The number of units in a real estate property owned as of the balance sheet date. + References No definition available. + Details
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- Details
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- Details
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- Details
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