Investments (Equity Method Investees Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Schedule Of Equity Method Investments [Line Items]
Equity method investment carrying value	$ 139,510	$ 141,506
Impairment loss on investment	0	0	$ 0
Dividends received from affiliates	$ 10,927	$ 12,243	$ 11,447
Hexavest [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment ownership percentage	49.00%	49.00%
Equity method investment carrying value	$ 136,000	$ 138,000
Private Equity Partnership [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment ownership percentage	7.00%	7.00%
Equity method investment carrying value	$ 3,500	$ 3,500

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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