Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Fair Value, Option, Quantitative Disclosures [Line Items]
Transfers between Level 1, 2 and 3 in fair value measurement hierarchy	$ 0	$ 0
Unfunded commitments	10,242,000	$ 18,676,000
EGCP III [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Unfunded commitments	$ 9,672,000
End of the investment period	Oct. 12, 2016
Remaining commitments date	Oct. 12, 2023

Expiration date of the option.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Footnote 5

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- Definition

Fair Value Transfers Between Level One Level Two And Level Three Amount

+ References

No definition available.

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- Definition

Remaining commitment date

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No definition available.

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=SL6742756-110258

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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.

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