Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Details) - USD ($) $ in Thousands	Aug. 31, 2019	Nov. 30, 2018
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 573,457	$ 322,909
Unfunded Commitments	19,154	20,996
Equity Long/Short Hedge Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	292,205	15,338
Unfunded Commitments	$ 0	$ 0
Percentage of investment at fair value, redemption restriction	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	$ 33,891	$ 40,070
Unfunded Commitments	$ 19,154	20,996
Expected period for the liquidation of the underlying assets, minimum	1 year
Expected 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	$ 15,212	10,129
Unfunded Commitments	$ 0	$ 0
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	$ 231,991	$ 256,972
Unfunded Commitments	$ 0	$ 0
Percentage of redeemable investments	4.00%	15.00%
Notice period redemption of investment prior written notice period	30 days	30 days
Other Funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 158	$ 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 redeemable investments	6.00%	97.00%
Notice period redemption of investment prior written notice period	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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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=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
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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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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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-SubTopic 10
-Section 50
-Paragraph 6A
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-URI http://asc.fasb.org/extlink&oid=99377789&loc=SL6742756-110258

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