Non-operating income (expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jan. 31, 2020	Jan. 31, 2019
Interest and other income	$ 9,336	$ 9,820
Net gains (losses) on investments and derivatives	7,000	(3,646)
Net foreign currency losses	(246)	(341)
Gains and other investment income, net	16,090	5,833
Interest expense	(5,888)	(6,131)
Other income (expense) of consolidated collateralized loan obligation (CLO) entities:
Interest income	24,905	11,750
Net gains (losses) on bank loans and other investments and note obligations	(9,342)	(6,309)
Gains and other investment income, net	15,563	5,441
Structuring and closing fees	(236)	(101)
Interest expense	(17,160)	(8,235)
Interest and other expense	(17,396)	(8,336)
Total non-operating income (expense)	$ 8,369	$ (3,193)