v3.20.4

Financial Highlights (Net Investment Income Ratio to Average Equity) (Details) | 12 Months Ended
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Dec. 31, 2018
Investment Company, Financial Highlights [Abstract] |
Investment Company, Investment Income (Loss) Ratio | 7.04%

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- Definition Percentage of investment income (loss) to average net assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 205 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=25866437&loc=d3e10328-115837 + Details
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