Income Taxes - Total Income Taxes (Detail) - CAD ($) $ in Millions	12 Months Ended
Oct. 31, 2025	Oct. 31, 2024
Provision for (reversal of) current income taxes
Adjustments for prior years	$ 15	$ (38)
Current income tax expense	2,727	2,294
Total provision for (reversal of) current income taxes	2,742	2,256
Provision for (reversal of) deferred income taxes
Adjustments for prior years	(11)	37
Effect of changes in tax rates and laws	2	4
Origination and reversal of temporary differences	(248)	(285)
Total provision for (reversal of) deferred income taxes	(257)	(244)
Income tax expense	2,485	2,012
OCI	397	578
Total comprehensive income	$ 2,882	$ 2,590

Income tax relating to comprehensive income

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Adjustments of tax expense (income) recognised in the period for current tax of prior periods.

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Adjustments of tax expense (income) recognised in the period for the deferred tax of prior periods.

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The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period.

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The amount of current tax expense (income) and adjustments for the current tax of prior periods. [Refer: Current tax expense (income); Adjustments for current tax of prior periods]

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The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

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The amount of deferred tax expense or income relating to the creation or reversal of temporary differences. [Refer: Temporary differences [member]; Deferred tax expense (income)]

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The amount of deferred tax expense or income relating to tax rate changes or the imposition of new taxes. [Refer: Deferred tax expense (income)]

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income]

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