Other Liabilities and Deferred Credits (Details) - CAD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Other liabilities and deferred credits
Personal injury and other claims provisions	$ 232	$ 238
Environmental provisions	18	13
Stock-based compensation liability	9	14
Contract liabilities	0	85
Deferred credits and other	168	184
Total other liabilities and deferred credits	$ 427	$ 534

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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