Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Detail) - USD ($) $ in Thousands	Feb. 28, 2018	Nov. 30, 2017
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 327,477	$ 215,385
Unfunded Commitments	18,176	19,084
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	34,623	33,176
Unfunded Commitments	$ 0	$ 0
Percentage of investment at fair value in liquidation	1.00%	1.00%
Fixed Income and High Yield Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 405	$ 417
Unfunded Commitments	0	0
Fund of Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	186	189
Unfunded Commitments	0	0
Private equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	32,839	26,798
Unfunded Commitments	$ 18,176	$ 19,084
Estimated period for the liquidation of the underlying assets, minimum	1 year	1 year
Estimated period for the liquidation of the underlying assets, maximum	6 years	6 years
Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 259,424	$ 154,805
Unfunded Commitments	$ 0	$ 0
Percentage of redeemable investments	17.00%	12.00%
Notice period redemption of investment prior written notice period	30 days	30 days

Estimated period for the liquidation of the underlying assets, maximum.

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Estimated period for the liquidation of the underlying assets, Minimum.

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- Definition

Investments at fair value that cannot be redeemed at reporting date and are subject to a prior written redemption request.

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No definition available.

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- Definition

Percentage of Investment at Fair Value in Liquidation

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No definition available.

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- Definition

Investments redeemable within 60-90 days

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No definition available.

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- Definition

Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258

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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.

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No definition available.

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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=66048111&loc=SL6742756-110258

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