Post Retirement Benefit Plans - Actuarial Assumptions Used for the Measurement of Benefit Obligations and Pension Costs (Details) - Other Postretirement Benefits Plan	Oct. 31, 2019	Oct. 31, 2018
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Actuarial assumptions used to measure the year-end benefit obligations and the pension costs	3.52%	5.02%
United States
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Actuarial assumptions used to measure the year-end benefit obligations and the pension costs	2.95%	4.39%
South Africa
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Actuarial assumptions used to measure the year-end benefit obligations and the pension costs	9.20%	10.10%