Subordinated indebtedness - Additional Information (Detail) - CAD ($) $ in Billions	Apr. 19, 2021	Jan. 26, 2021
Disclosure Of Subordinated Indebtedness [Line Items]
Debentures principal amount		$ 1.0
Interest rate		3.42%
Borrowings maturity		January 26, 2026
Debentures terms of interest payment		the Debentures were redeemed at 100% of their principal amount, plus accrued and unpaid interest
April 19 2021 [member]
Disclosure Of Subordinated Indebtedness [Line Items]
Debentures principal amount	$ 1.0
Interest rate	1.96%
Borrowings maturity	April 21, 2031
Fixed interest rate till april 21 2026 [member] \| April 21 2031 [member]
Disclosure Of Subordinated Indebtedness [Line Items]
Interest rate	1.96%
Borrowings, interest rate basis	fixed rate of 1.96% per annum
Interest periodic payment	semi-annually
Three month CDOR term [member] \| April 21 2031 [member]
Disclosure Of Subordinated Indebtedness [Line Items]
Interest rate	0.56%
Borrowings, interest rate basis	three-month CDOR plus 0.56% per annum
Interest periodic payment	quarterly

Borrowings interest frequency of periodic payment.

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- Definition

Borrowings terms of interest payment.

+ References

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- Definition

Disclosure of subordinated indebtedness [Line Items].

+ References

No definition available.

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- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 7
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The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

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- Definition

The maturity of borrowings. [Refer: Borrowings]

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- Definition

The amount of subordinated liabilities that have a specified repayment date. [Refer: Subordinated liabilities]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
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-URIDate 2020-01-01

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