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Commitments and Contingencies - Additional Information (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 USD ($) Property ApartmentUnit | Dec. 31, 2016 USD ($)
Accrual for Environmental Loss Contingencies | $ 300,000 | $ 4,700,000
Loss Contingency Accrual, Period Increase (Decrease) | 0 |
Loss Contingency Accrual | $ 1,000,000 |
Projects in various stages of development | Property | 5 |
Units in various stages of development | ApartmentUnit | 1,720 |
Consolidated Project Under Development Commitment Fund | $ 191,200,000 |
Various stages of development with estimated completion dates ranging through September 30, 2017 | Dec. 31, 2018 |
Partially Owned Properties – Unconsolidated |  |
Number Of Unconsolidated Projects | Property | 2 |

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- Definition Represents the company's remaining funding obligation (i.e. total project costs less book value) for consolidated projects that are under development. + References No definition available. + Details
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Balance Type: | debit
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X
- Definition Total number of open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. These projects are consolidated. + References No definition available. + Details
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- Definition Total number of unconsolidated open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. + References No definition available. + Details
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- Definition Total number of units that are associated with open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. These units are consolidated. + References No definition available. + Details
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- Definition Represents the latest completion date for the current projects under development. + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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- Definition Amount of loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 + Details
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- Definition Amount of increase (decrease) in loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 + Details
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- Details
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