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Significant Accounting Policies - Assets under Management (AUM) Subject to Incentive Fees and Incentive Fees (Detail)	9 Months Ended
	Sep. 30, 2016 USD ($)
Principal Transaction Revenue [Line Items]
AUM Subject to Incentive Fees	$ 590,718,723
Incentive Fees Under Method 2
Principal Transaction Revenue [Line Items]
Performance incentive fees	3,173,989
Incentive Fees Under Method 2 | Quarter Ended June 30, 2017
Principal Transaction Revenue [Line Items]
Performance incentive fees	2,756,586
Incentive Fees Under Method 2 | Quarter Ended December 31, 2018
Principal Transaction Revenue [Line Items]
Performance incentive fees	71,108
Incentive Fees Under Method 2 | Quarter Ended September 30, 2019
Principal Transaction Revenue [Line Items]
Performance incentive fees	346,295
Incentive Fees Under Method 2 | Quarter Ended March 31, 2020
Principal Transaction Revenue [Line Items]
Performance incentive fees	$ 0

X

- Definition

Assets under management (AUM) subject to incentive fees and incentive fees.

+ References

No definition available.

+ Details

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X

- Definition

Amount of revenue earned by the entity based on the investment results achieved. Excludes fees based upon a percentage of the assets under management not performance-related.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13 (a))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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- Definition

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+ References

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