Other Long-Term Liabilities (Details) - CAD ($) $ in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
Operating lease liabilities, net of current portion	$ 285		$ 0
Stock-based compensation liabilities, net of current portion	111		81
Provision for environmental remediation, net of current portion	70		74
Deferred revenue on rights-of-way license agreements, net of current portion	20		24
Deferred gains on sale leaseback transactions	6		13
Other, net of current portion	70		45
Total other long-term liabilities	562	$ 574	237
Aggregate provision for environmental remediation, including current portion	$ 77		$ 82

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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