Income Taxes - Components of Income Tax Expense (Recovery) Recognized in Consolidated Statements of Income (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Current tax
Current year	$ 1,097	$ 1,390
Adjustments related to prior year	(263)	(50)
Current tax	834	1,340
Deferred tax
Change related to temporary differences	706	(139)
Adjustments related to prior years	226	12
Effects of change in tax rates in Canada	(201)
Total deferred tax	731	(127)
Income tax expense	$ 1,565	$ 1,213

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 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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