Investment in Real Estate Properties - Summary of Intangible Lease Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Intangible Lease Assets [Member]
Finite-Lived Intangible Assets And Liabilities [Line Items]
Gross	$ 334,950	$ 347,186
Accumulated Amortization	(150,812)	(106,872)
Net	184,138	240,314
Above-Market Lease Assets [Member]
Finite-Lived Intangible Assets And Liabilities [Line Items]
Gross	40,362	43,623
Accumulated Amortization	(19,878)	(14,453)
Net	20,484	29,170
Below-Market Lease Liabilities [Member]
Finite-Lived Intangible Assets And Liabilities [Line Items]
Gross	(37,177)	(37,621)
Accumulated Amortization	10,016	5,763
Net	$ (27,161)	$ (31,858)

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Amount of accumulated amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of 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)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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