Investments - Jefferies LoanCore - Narrative (Detail) - USD ($) $ in Thousands	12 Months Ended
	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2014	Mar. 31, 2016
Guarantor Obligations [Line Items]
Equity commitment	$ 600,000
Jefferies LoanCore, LLC [Member]
Guarantor Obligations [Line Items]
Aggregate commitment	400,000	$ 600,000
Funded portion of equity commitment to subsidiary	70,100	207,400
Equity commitment	$ 194,000	291,000
Ownership percentage	48.50%
Net earnings from equity method investment	$ 71,800	79,000	$ 38,700
Reimbursed administrative services	200	200	100
Receivables under service agreement	16	16
Placement fees earned	$ 100	$ 1,600	$ 1,600
Jefferies LoanCore, LLC [Member] | Canada Pension Plan Investment Board [Member]
Guarantor Obligations [Line Items]
Equity Method Investment, Ownership Percentage by Third Party				24.00%