Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Feb. 28, 2021	Nov. 30, 2020
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 1,017,822	$ 955,984
Unfunded Commitments	32,793	16,242
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	345,570	328,096
Unfunded Commitments	$ 0	$ 0
Fair value, investments, entities that calculate net asset value per share, redemption restriction, percentage	94.00%	94.00%
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 redeemable investments	6.00%	6.00%
Notice period redemption of investment prior written notice period	60 days	60 days
Equity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 23,856	$ 23,821
Unfunded Commitments	$ 11,043	$ 11,242
Estimated period for the liquidation of the underlying assets, minimum	1 year	1 year
Expected 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	$ 19,217	$ 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 period	60 days	60 days
Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 580,269	$ 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 redeemable investments	57.00%	57.00%
Notice period redemption of investment prior written notice period	60 days	60 days
Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 48,910	$ 25,084
Unfunded Commitments	$ 21,750	$ 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 period	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 period	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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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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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
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258

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