Post-Employment Benefits - Summary of Assumed Health-care Cost Trend Rates (Detail) - Canada plan [member] - Actuarial assumption of medical cost trend rates [member]	12 Months Ended
Oct. 31, 2018	Oct. 31, 2017
Disclosure of defined benefit plans [line items]
Health-care cost trend rates assumed for next year	5.30%	5.70%
Rate to which the cost trend rate is assumed to decline	4.00%	4.50%
Year that the rate reaches the ultimate trend rate	2040	2029

Actuarial assumption of year rate reach ultimate trend rate.

No definition available.

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- Definition

Medical cost trend rate used as significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 144
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_144&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 145
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_145_a&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Details

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- Details

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