Fair Value Disclosures - Investments Measured at Fair Value Based on Net Asset Value Per Share (Footnote) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Aug. 31, 2015	Aug. 31, 2014	Nov. 30, 2014
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Increase in funds	$ (14,508)	$ (9,957)
Equity Long/Short Hedge Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of redeemable investments	100.00%		99.00%
Fixed Income and High Yield Hedge Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments with no redemption provisions	7.00%		8.00%
Increase in funds	$ 2,500
Fund of Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Percentage of investments with no redemption provisions	95.00%		95.00%
Estimated period for the liquidation of the underlying assets, Maximum	16 months
Private equity funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Estimated period for the liquidation of the underlying assets, Maximum	8 years
Percentage of investments at fair value expected to liquidate	100.00%		99.00%
Estimated period for the liquidation of the underlying assets, Minimum	1 year
Minimum [Member] | Equity Long/Short Hedge Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice period	30 days
Maximum [Member] | Equity Long/Short Hedge Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Notice period redemption of investment prior written notice period	90 days