Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Details) - USD ($) $ in Thousands	12 Months Ended
Nov. 30, 2019	Nov. 30, 2018
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 570,310	$ 322,909
Unfunded Commitments	12,108	20,996
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	291,593	15,338
Unfunded Commitments	$ 0	$ 0
Percentage of investments in liquidation	94.00%	0.00%
Investments redemption restriction period	36 months
Equity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 27,952	$ 40,070
Unfunded Commitments	$ 12,108	$ 20,996
Estimated period for the liquidation of the underlying assets, minimum	1 year	1 year
Estimated period for the liquidation of the underlying assets, maximum	9 years
Commodity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 16,025	$ 10,129
Unfunded Commitments	$ 0	0
Notice period redemption of investment prior written notice	60 days
Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 234,583	256,972
Unfunded Commitments	$ 0	$ 0
Percentage of investments redeemable	5.00%	15.00%
Notice period redemption of investment prior written notice	30 days
Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 157	$ 400
Unfunded Commitments	$ 0	$ 0
60 Days Prior Written Notice \| Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments redeemable	6.00%	97.00%
Notice period redemption of investment prior written notice	60 days

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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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Percentage of Investment at Fair Value in Liquidation

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Investments redeemable within 60-90 days

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No definition available.

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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.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 35
-Paragraph 54B
-URI http://asc.fasb.org/extlink&oid=99392525&loc=SL7495116-110257

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