Share-Based Compensation (Details) - CAD CAD in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
SHARE BASED COMPENSATION
Equity-settled plans	CAD 48	CAD 48
Cash-settled plans	334	395
Total share-based compensation expense	CAD 382	CAD 443

No definition available.

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- Definition

The amount of expense arising from cash-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions in which goods or services received did not qualify for recognition as assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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- Definition

The amount of expense arising from equity-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions in which goods or services received did not qualify for recognition as assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of expense arising from share-based payment transactions in which the goods or services received did not qualify for recognition as assets.

+ References

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