Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Detail) - USD ($) $ in Thousands			6 Months Ended
May 31, 2019	Nov. 30, 2018	May 31, 2019
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 566,134	$ 322,909	$ 566,134
Unfunded Commitments	19,679	20,996	19,679
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	280,761	15,338	280,761
Unfunded Commitments	$ 0	$ 0	$ 0
Percentage of investment at fair value, redemption restriction	94.00%	0.00%	94.00%
Investments redemption restriction period			36 months
Investments redemption restriction period remaining			31 months
Equity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 35,863	$ 40,070	$ 35,863
Unfunded Commitments	$ 19,679	$ 20,996	19,679
Expected period for the liquidation of the underlying assets, minimum	1 year	1 year
Expected period for the liquidation of the underlying assets, maximum	10 years	10 years
Commodity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 15,672	$ 10,129	15,672
Unfunded Commitments	$ 0	$ 0	0
Notice period redemption of investment prior written notice period	60 days	60 days
Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 233,512	$ 256,972	233,512
Unfunded Commitments	$ 0	$ 0	$ 0
Notice period redemption of investment prior written notice period	30 days	30 days
Percentage of redeemable investments	5.00%	15.00%	5.00%
Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 326	$ 400	$ 326
Unfunded Commitments	$ 0	$ 0	$ 0
45 - 90 days prior written notice \| Equity Long/Short Hedge Funds \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice period	45 days
45 - 90 days prior written notice \| Equity Long/Short Hedge Funds \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice period	90 days
60 days prior written notice \| Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice period	60 days
Percentage of redeemable investments	6.00%	97.00%	6.00%

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Expected Period For Liquidation Of Underlying Assets Minimum

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

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Investments redeemable within 60-90 days

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
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-URI http://asc.fasb.org/extlink&oid=99377789&loc=SL6742756-110258

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-Publisher FASB
-Name Accounting Standards Codification
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The percentage of the total value of investments that cannot be redeemed because of a redemption restriction as of the statement of financial position date.

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Remaining period of a redemption restriction related to investments for which net asset value per share is calculated, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Period when redemption restriction has been in effect for investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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).

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