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Investment in Unconsolidated Ventures - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2015 | Mar. 31, 2014
Schedule of Equity Method Investments [Line Items] |  |
Investment in unconsolidated ventures | $ 831 us-gaap_PaymentsToAcquireInterestInJointVenture | $ 4,293 us-gaap_PaymentsToAcquireInterestInJointVenture
Distributions of return on investments and earnings | $ 3,500 for_DistributionsOfReturnOnInvestmentsAndEarnings | $ 1,173 for_DistributionsOfReturnOnInvestmentsAndEarnings
Equity Method Investments [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Number of ventures under ownership interest using equity method | 15 us-gaap_NumberOfRealEstateProperties / us-gaap_FairValueByAssetClassAxis = us-gaap_EquityMethodInvestmentsMember |

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- Definition Distributions of return on investments and earnings. + References No definition available. + Details
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Balance Type: | debit
Period Type: | duration

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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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Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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- Definition The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585 + Details
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- Details
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Namespace Prefix: | us-gaap_
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |