Fair Value Disclosures - Investments at Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
May 31, 2022	May 31, 2022	Nov. 30, 2021
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 57,154	$ 57,154	$ 53,905
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0	$ 0	$ 0
Percentage of investment at fair value, redemption restriction	32.00%	32.00%	21.00%
Equity Long/Short Hedge Funds \| 90 Days Prior Written Notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investment at fair value, redemption restriction	63.00%	63.00%	74.00%
Notice period redemption of investments prior written notice period	90 days	90 days
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 investments prior written notice period	60 days	60 days
Equity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 41,191	$ 41,191	$ 17,815
Equity Funds \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Estimated period for the liquidation of the underlying assets	1 year	1 year
Equity Funds \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Estimated period for the liquidation of the underlying assets	13 years	13 years
Commodity Fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0	$ 0	0
Commodity Fund \| 60 Days Prior Written Notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investments prior written notice period	60 days	60 days
Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0	$ 0	$ 0
Multi-asset Funds \| 90 Days Prior Written Notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investment at fair value, redemption restriction	16.00%	16.00%	22.00%
Notice period redemption of investments prior written notice period	90 days	90 days
Multi-asset Funds \| 60 Days Prior Written Notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investment at fair value, redemption restriction	77.00%	77.00%	78.00%
Notice period redemption of investments prior written notice period	60 days	60 days
Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 15,963	$ 15,963	$ 36,090
Other Funds \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments outstanding period	90 days	90 days
Other Funds \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investments outstanding period	120 days	120 days
Other Funds \| 90 Days Prior Written Notice
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investments prior written notice period	90 days	90 days
Fair value measured at NAV
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 1,305,000	$ 1,305,000	1,025,940
Fair value measured at NAV \| Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	482,004	482,004	466,231
Fair value measured at NAV \| Equity Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	57,760	57,760	46,030
Fair value measured at NAV \| Commodity Fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	25,461	25,461	24,401
Fair value measured at NAV \| Multi-asset Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	418,397	418,397	390,224
Fair value measured at NAV \| Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 321,378	$ 321,378	$ 99,054

Estimated period for the liquidation of the underlying assets,

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- Definition

Investments Outstanding Period

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- Definition

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

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- Definition

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 https://asc.fasb.org/extlink&oid=126976982&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 https://asc.fasb.org/extlink&oid=126972413&loc=SL7495116-110257

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- Definition

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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).

+ References

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 https://asc.fasb.org/extlink&oid=126976982&loc=SL6742756-110258

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