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Income Taxes - Federal Income Tax Treatment of Common Dividends (Details) - Common Stock - $ / shares | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Income Tax [Line Items] |  |  |
Ordinary Income | $ 0.6552 | $ 0.6935 | $ 0.2629
Unrecaptured Section 1250 Gain | 0.1627 | 0.1130 | 0.1241
Capital Gain | 0.0648 | 0.0066 | 0.0000
Nondividend Distribution - Return of Capital | 0.0000 | 0.0272 | 0.0000
Distributions Per Common Share | $ 0.8827 | $ 0.8403 | $ 0.3870
Ordinary Income as a Percentage of Distribution | 74.23% | 82.53% | 67.93%
Unrecaptured Section 1250 Gain as a Percentage of Distribution | 18.43% | 13.45% | 32.07%
Capital Gain as Percentage of Distributions | 7.34% | 0.78% | 0.00%
Nondivided Distribution - Return of Capital As Percentage Of Distributions | 0.00% | 3.24% | 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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