Other Liabilities and Deferred Credits (Details) - CAD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Other liabilities and deferred credits
Personal injury and other claims provisions	$ 249	$ 234
Environmental provisions	22	21
Stock-based compensation liability	19	26
Deferred credits and other	211	309
Total other liabilities and deferred credits	$ 501	$ 590

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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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

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Carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income after one year or beyond the normal operating cycle, if longer and noncurrent obligations not separately disclosed in the balance sheet (other liabilities, noncurrent).

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Aggregated carrying amounts of obligations as of the balance sheet date, excluding long-term debt, incurred as part of the normal operations that are expected to be paid after one year or beyond the normal operating cycle, if longer. Alternate captions include Total Deferred Credits and Other Liabilities.

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Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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