Financial Instruments-Risk Management - Summary of Credit Risk Exposures (Parenthetical) (Detail) - CAD ($) $ in Millions	Oct. 31, 2021	Oct. 31, 2020
Disclosure of detailed information about financial instruments [abstract]
Loss balance sheet offsetting lending instruments	$ 22.3	$ 27.6

Derivatives transactions net of related collateral .

No definition available.

Name:	bns_DerivativesTransactionsNetOfRelatedCollateral
Namespace Prefix:	bns_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant