Stock-Based Compensation Plans (Summary of stock-based compensation expense recognized by plan) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		$ 239,286	$ 91,913	$ 88,055
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		140,700
Employee Stock Purchase Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		525	355	793
Employee Stock Purchase Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		1,096	512	877
Omnibus Incentive Plans [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		209,217	57,821	52,312
Omnibus Incentive Plans [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		23,234	21,949	23,531
Omnibus Incentive Plans [Member] | Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		1,745	915	1,008
Atlanta Capital Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		1,604	2,280	2,969
Atlanta Capital Phantom Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		1,810	1,087	567
Parametric Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 1,600	0	3,461	3,177
Parametric Phantom Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		$ 55	$ 3,533	$ 2,821