Other Liabilities and Deferred Credits (Details) - CAD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Other liabilities and deferred credits
Personal injury and other claims provisions	$ 238	$ 261
Contract liabilities	85	161
Stock-based compensation liability	14	16
Environmental provisions	13	19
Deferred credits and other	184	177
Total other liabilities and deferred credits	$ 534	$ 634

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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