v3.8.0.1

Financial Highlights (Net Investment Income Ratio To Average Equity) (Details)

3 Months Ended

9 Months Ended

Sep. 30, 2017

Sep. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Investment Company, Financial Highlights [Abstract]

Net Investment Income (Loss) Ratio

^[1],[2]

4.95%

3.80%

5.86%

5.14%

[1]	Average equity is calculated using month end values.
[2]	Includes all items of income and expense on an annualized basis.

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- References

No definition available.

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- Definition

Percentage of investment income (loss) to average net assets.

+ References

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

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