v3.19.1

Financial Highlights (Net Asset Value Based Total Return for a Shareholder) (Details)	3 Months Ended
	Mar. 31, 2018
Investment Company, Financial Highlights [Abstract]
Total Return	4.30%

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- References

No definition available.

+ Details

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- Definition

Percentage increase (decrease), after deduction of incentive fee, in fund net asset value. Includes, but is not limited to, interest and dividend income (loss) and realized and unrealized gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 205
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=25866437&loc=d3e10421-115837

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