Employee Benefits - Summary of Sensitivity Analysis of Impact on Employee Future Benefit Liabilities (Detail) $ in Millions	Jan. 31, 2019 CAD ($)
Actuarial assumption of discount rates [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase (Decrease) of liabilities due to increase in actuarial assumption	$ (34.6)
Increase (Decrease) of liabilities due to decrease in actuarial assumption	38.8
Actuarial assumption of expected rates of salary increases [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase (Decrease) of liabilities due to increase in actuarial assumption	9.2
Increase (Decrease) of liabilities due to decrease in actuarial assumption	(8.6)
Actuarial assumption of life expectancy after retirement [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase (Decrease) of liabilities due to increase in actuarial assumption	9.1
Increase (Decrease) of liabilities due to decrease in actuarial assumption	$ (9.3)

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.

No definition available.

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 145
-Subparagraph a
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-URIDate 2018-03-16

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

+ References

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