Variable Interest Entities (Summary of the amounts related to vie that are consolidated on the company's income statement) (Details) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Other income (expense) of consolidated CLO entities:
Gains and other investment income, net	$ 36,123	$ 70,272	$ 16,882
Interest and other expense	(55,201)	(59,350)	(15,286)
Consolidated Securitized CLO Entities [Member]
Other income (expense) of consolidated CLO entities:
Gains and other investment income, net	36,527	66,964	10,264
Interest and other expense	(55,104)	(57,860)	(11,796)
Net gain (loss) attributable to the Company	$ (18,577)	$ 9,104	$ (1,532)