Summary of Significant Accounting Policies - Net Amortization Expense Related to Deferred Leasing Intangibles (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Estimated Net Increase to Rental Revenues Related to Above and Below Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
2013	$ 631
2014	472
2015	455
2016	968
2017	908
Amortization of In-Place Leases and Tenant Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
2013	5,584
2014	4,551
2015	3,750
2016	2,615
2017	$ 2,227

Future Estimated Real Estate Revenue Increase Next Twelve Months.

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Future estimated real estate revenue increase year five.

+ References

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Future estimated real estate revenue increase year four.

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Future estimated real estate revenue increase year three.

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Future estimated real estate revenue increase year two.

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Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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