Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Restricted cash	$ 6,133,403	$ 5,568,405
Cash denominated in foreign currencies	634,874	196,753
Cash denominated in foreign currencies, cost	642,300	$ 191,327
Provision for income tax	0
Uncertain tax position	$ 0
Open tax year	2015 2016 2017 2018

Cash held in fund denominated in foreign currency.

No definition available.

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- Definition

Cash held in fund denominated in foreign currency at cost.

+ References

No definition available.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (h)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (SX 210.4-08(h))
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-Section 45
-Paragraph 2
-Subparagraph (a)
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- Definition

Amount recognized for uncertainty in income taxes classified as current.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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