Other Liabilities and Deferred Credits (Details) - CAD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Other liabilities and deferred credits
Personal injury and other claims provisions	$ 261	$ 249
Contract liabilities	161	0
Environmental provisions	19	22
Stock-based compensation liability	16	19
Deferred credits and other	177	211
Total other liabilities and deferred credits	$ 634	$ 501

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

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