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Income Taxes - Federal Income Tax Treatment of Share Distributions (Detail) - Common Stock - $ / shares | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Income Tax [Line Items] |  |  |
Ordinary Income | $ 0.2629 | $ 0.4412 | $ 0.3088
Unrecaptured Section 1250 Gain | 0.1241 | 0.0000 | 0.0000
Distributions Per Common Share | $ 0.3870 | $ 0.4412 | $ 0.3088
Ordinary Income as a Percentage of Distribution | 67.93% | 100.00% | 100.00%
Unrecaptured Section 1250 Gain as a Percentage of Distribution | 32.07% | 0.00% | 0.00%
Common Distributions Percentage | 100.00% | 100.00% | 100.00%

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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