Income Taxes (Reconciliation of Income Tax Expense) (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income tax expense reconciliation
Canadian statutory federal tax rate	15.00%	15.00%	15.00%
Income tax expense at the Canadian statutory federal tax rate	$ 852	$ 763	$ 739
Income tax expense (recovery) resulting from:
Provincial and foreign taxes	535	536	532
Deferred income tax adjustments due to rate enactments	0	(1,706)	7
Gain on disposals	(51)	(3)	(12)
Other	18	15	21
Income tax expense (recovery)	1,354	(395)	1,287
Net cash payments for income taxes	$ 776	$ 712	$ 653

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The portion of the difference, between total income tax expense (benefit) as reported in the Income Statement for the period and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to provincial and foreign federal, state and local income tax expense (benefit).

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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