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           Stockholders' Equity - Monthly Distributions Declared and Paid by Company's Board of Directors (Detail) (USD $) 
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        3 Months Ended | |
|---|---|---|
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           Mar. 31, 2014 
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           Mar. 31, 2013 
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| Equity [Abstract] | ||
| Dividend Distribution per Share | $ 0.09 | $ 0.08 | 
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- Definition 
          Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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