Cash and Cash Equivalents - Schedule Representing Cash and Cash Equivalents (Detail) - CAD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash And Cash Equivalents [Abstract]
Cash	$ 155	$ 547
Short-Term Investments	626	63
Total	$ 781	$ 610	$ 3,720	$ 4,105

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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