Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Details) - USD ($) $ in Thousands	12 Months Ended
Nov. 30, 2021	Nov. 30, 2020
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 1,012,322	$ 955,984
Unfunded Commitments	46,683	16,242
Equity long/short hedge funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	466,231	328,096
Unfunded Commitments	$ 0	$ 0
Equity long/short hedge funds \| Period one
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value, investments, entities that calculate net asset value per share, redemption restriction, percentage	74.00%	94.00%
Equity long/short hedge funds \| Period two
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments redeemable	21.00%
Equity long/short hedge 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
Equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 32,412	$ 23,821
Unfunded Commitments	$ 10,593	$ 11,242
Estimated period for the liquidation of the underlying assets, minimum	1 year	1 year
Estimated period for the liquidation of the underlying assets, maximum	7 years	7 years
Commodity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 24,401	$ 17,747
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	$ 390,224	$ 561,236
Unfunded Commitments	$ 0	$ 0
Multi-asset funds \| 60 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments redeemable	78.00%	57.00%
Notice period redemption of investment prior written notice	60 days	60 days
Multi-asset funds \| 90 Days prior written notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments redeemable	22.00%
Notice period redemption of investment prior written notice	90 days
Other funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair value	$ 99,054	$ 25,084
Unfunded Commitments	$ 36,090	$ 5,000
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	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	120 days

Expected Period For Liquidation Of Underlying Assets Maximum

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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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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
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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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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
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-Paragraph 6A
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