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Summary of Significant Accounting Policies - Additional Information (Details) | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Feb. 28, 2017 USD ($) | Mar. 31, 2018 USD ($) Property ApartmentUnit | Mar. 31, 2017 USD ($) | Dec. 31, 2017 USD ($)
Provision for income tax |  | $ 213,000 | $ 262,000 |
Percentage of rental income excluded from accounting standard adoption |  | 94.00% |  |
Percentage of total revenue subject to revenue recognition standard |  | 6.00% |  |
Properties | Property |  | 303 |  |
Apartment Units | ApartmentUnit |  | 78,399 |  |
Noncontrolling interests partially owned properties |  | $ 1,293,000 |  | $ 4,708,000
Partially Owned Properties – Consolidated |  |  |  |
Properties | Property |  | 17 |  |
Apartment Units | ApartmentUnit |  | 3,535 |  |
Limited Life Partnership Properties [Member] |  |  |  |
Properties | Property |  | 4 |  |
Noncontrolling interests equity (deficit) partially owned properties |  | $ 8,700,000 |  |
Noncontrolling interests settlement value |  | 66,300,000 |  |
Adjustments for New Accounting Principle, Early Adoption |  |  |  |
Gain (loss) on equity transaction | $ 0 |  |  |
Federal [Member] |  |  |  |
Provision for income tax |  | $ 0 |  |

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- Definition Represents the value of Noncontrolling Interest distributions had the Company's partnership agreements been liquidated through the sale of their assets upon reaching the date specified in each respective partnership agreement. The Company, as controlling partner, has an obligation to cause the property owning partnerships to distribute the proceeds of liquidation to the Noncontrolling Interests in these Partially Owned Properties. + References No definition available. + Details
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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