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- Definition

Merger Related Expenses

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- Definition

Property Held for Development

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- Definition

Percentage Of Ownership Interests

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No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

The number of general partner units outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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- Definition

The number of states the entity operates in as of the balance sheet date.

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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- Definition

The book value of investments in real estate joint ventures including direct and indirect investments.

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-Name Accounting Standards Codification
-Topic 944
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Consolidation and Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) shares	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) shares	Sep. 30, 2017 Property	Sep. 30, 2017 States	Sep. 30, 2017 $ / shares	Sep. 30, 2017 Communities	Sep. 30, 2017 USD ($)	Sep. 30, 2017 shares	Sep. 30, 2017 ft²	Dec. 31, 2016 USD ($) $ / shares
Real Estate Properties [Line Items]
General Partners' Capital Account, Units Outstanding \| shares		75,542,583		75,542,583						113,627,014
Limited Liability (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest			96.40%
Preferred Stock, Dividend Rate, Percentage			8.50%
Number of owned or owned interests of apartment communities					303			302
Number of states in which apartment units are located \| States						17
Percentage Of Ownership Interests	100.00%		100.00%
Minimum [Member]
Real Estate Properties [Line Items]
Percentage Of Ownership Interests	92.50%		92.50%
Maximum [Member]
Real Estate Properties [Line Items]
Percentage Of Ownership Interests	100.00%		100.00%
Development Properties [Member]
Real Estate Properties [Line Items]
Number of owned or owned interests of apartment communities \| Communities								5
Number of units under development community \| Property					1,434
Development Properties [Member] \| Expected Costs [Member]
Real Estate Properties [Line Items]
Development and capital improvements in progress									$ 305,000
Development Properties [Member] \| Costs Incurred to Date [Member]
Real Estate Properties [Line Items]
Development and capital improvements in progress									235,300
Retail
Real Estate Properties [Line Items]
Number of owned or owned interests of apartment communities \| Property					29
Square Footage of Real Estate Property \| ft²											600,000
Commercial Real Estate [Member]
Real Estate Properties [Line Items]
Square Footage of Real Estate Property \| ft²											232,000
Real Estate Technology Ventures, L.P. [Member]
Real Estate Properties [Line Items]
Equity Method Investment, Ownership Percentage	32.00%		32.00%
Real Estate Investments, Joint Ventures									800
Real Estate Technology Ventures, L.P. [Member] \| Limited Partner Capital Contribution, Future Obligation [Member]
Real Estate Properties [Line Items]
Real Estate Investments, Joint Ventures									14,200
Post River North [Member]
Real Estate Properties [Line Items]
Number of apartments included in a community	358		358
Development and capital improvements in progress									60,300
Percentage Of Ownership Interests	92.50%		92.50%
Land									14,500
Accrued expenses and other liabilities									6,200
Post Massachusetts Avenue [Member]
Real Estate Properties [Line Items]
Equity Method Investment, Ownership Percentage	35.00%		35.00%
Real Estate Investments, Joint Ventures									45,100
Parent Company [Member]
Real Estate Properties [Line Items]
Preferred Stock, Par or Stated Value Per Share \| $ / shares							$ 0.01					$ 0.01
Merger Related Expenses	$ 128	$ 3,901	$ 3,977	$ 3,901
Development and capital improvements in progress									156,938			$ 231,224
Land									1,828,637			1,816,008
Accrued expenses and other liabilities									$ 439,662			$ 414,244