Investment in Unconsolidated Joint Ventures - Summary of Unconsolidated Joint Ventures (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014 Building	Dec. 31, 2013
Investments in and Advances to Affiliates [Line Items]
Number of buildings	2
Investment in unconsolidated joint ventures	$ 8,207	$ 8,066
Park 355 DC II [Member]
Investments in and Advances to Affiliates [Line Items]
Number of buildings	1
Investment in unconsolidated joint ventures	3,967	3,791
Ownership percentage	75.00%
Valley Parkway [Member]
Investments in and Advances to Affiliates [Line Items]
Number of buildings	1
Investment in unconsolidated joint ventures	$ 4,240	$ 4,275
Ownership percentage	50.00%

The number of real estate properties owned as of the balance sheet date through an unconsolidated joint venture.

No definition available.

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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