Related Party Transactions (Sponsored Funds Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Oct. 31, 2019
Sponsored Funds
Management fees waived by the Company	$ 5.5	$ 4.3
Related party expenses all-in-management fee (excluding investment advisory and administrative fees)	3.2	3.4
Sponsored Funds [Member]
Sponsored Funds
Subsidies fees waived by the Company	5.4	$ 9.2
Included in management fees and other accounts receivable	109.9		$ 104.1
Included in accounts payable and accrued expenses	$ 2.2		$ 2.2