Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Details) - USD ($) $ in Thousands	12 Months Ended
Nov. 30, 2020	Nov. 30, 2019
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 955,984	$ 570,310
Unfunded Commitments	16,242	12,108
Equity long/short hedge funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	328,096	291,593
Unfunded Commitments	$ 0	$ 0
Fair value, investments, entities that calculate net asset value per share, redemption restriction, percentage	94.00%	94.00%
Investments redemption restriction period	36 months	36 months
Equity long/short hedge funds \| 60 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments redeemable	6.00%	6.00%
Notice period redemption of investment prior written notice	60 days	60 days
Equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 23,821	$ 27,952
Unfunded Commitments	$ 11,242	$ 12,108
Estimated period for the liquidation of the underlying assets, minimum	1 year	1 year
Estimated period for the liquidation of the underlying assets, maximum	8 years	8 years
Commodity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 17,747	$ 16,025
Unfunded Commitments	$ 0	$ 0
Commodity funds \| 60 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice	60 days	60 days
Multi-asset funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 561,236	$ 234,583
Unfunded Commitments	$ 0	$ 0
Percentage of investments redeemable	57.00%	5.00%
Multi-asset funds \| 60 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice	60 days	60 days
Multi-asset funds \| 30 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice	30 days	30 days
Other funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 25,084	$ 157
Unfunded Commitments	$ 5,000	$ 0
Short-term investments \| 90 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice	90 days
Short-term investments \| 120 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice	120 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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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.

+ 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=117815213&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=117332851&loc=SL7495116-110257

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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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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
-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=117815213&loc=SL6742756-110258

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