Investments - Jefferies LoanCore (Detail) - Jefferies LoanCore, LLC - USD ($) $ in Thousands		3 Months Ended
	Oct. 31, 2017	Feb. 28, 2017
Guarantee Obligations [Line Items]
Ownership percentage	48.50%
Proceeds from sale of Jefferies LoanCore	$ 173,100
Period entitled to additional cash consideration	5 years
Net earnings		$ 6,200
Interest income and fees		600
Service fees		$ 47