Other Liabilities and Deferred Credits (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Other liabilities and deferred credits
Personal injury and other claims provisions	CAD 234	CAD 225
Stock-based compensation liability	26	35
Environmental provisions	21	36
Deferred credits and other	309	297
Total other liabilities and deferred credits	CAD 590	CAD 593

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

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

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