Income Taxes (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
INCOME TAXES
Current year	$ 1,270	$ 1,150
Adjustments to current income tax of prior years	(20)	59
Origination and reversal of temporary differences	345	476
Adjustments in respect of deferred income tax of prior years	13	(70)
Changes in tax rates and legislation		(106)
Movement in unrecognized deferred income tax assets	82	(51)
Total tax expense (income)	$ 1,690	$ 1,458

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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