Stockholders Equity - Redemptions Table (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Stockholders' Equity Attributable to Parent [Abstract]
Number of eligible shares redeemed	1,480	700
Aggregate amount of shares redeemed	$ 14,814	$ 6,878
Average redemption price per share	$ 10.01	$ 9.83

The average redemption price per share of stock redeemed during period presented.

No definition available.

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- Details

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- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

+ References

+ Details

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