Supplementary Cash Flow Information - Summary of Supplementary Cash Flow Information (Detail) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure Of Supplementary Cash Flow Information [Abstract]
Interest Paid	$ 564	$ 538	$ 350
Interest Received	19	31	32
Income Taxes Paid	$ 116	$ 12	$ 11

Disclosure of supplementary cash flow information abstract.

No definition available.

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- Definition

The cash flows from income taxes paid or refunded.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Paragraph 35
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_35&doctype=Standard
-URIDate 2017-03-09

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- Definition

The cash outflow for interest paid, classified as operating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Paragraph 31
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_31&doctype=Standard
-URIDate 2017-03-09

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- Definition

The cash inflow from interest received, classified as operating activities.

+ References

+ Details

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