Consolidated statements of comprehensive income (Parenthetical) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Statement of comprehensive income [abstract]
Income tax relating to available-for-sale financial assets	$ 0	$ 0
Income tax relating to cash flow hedges	21	24
Income tax relating to actuarial (losses) gains of defined benefit plans	$ 92	$ 71

The amount of income tax relating to amounts recognised in other comprehensive income in relation to available-for-sale financial assets. [Refer: Financial assets available-for-sale; Other comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph ab
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-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-02&anchor=para_90&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph ab
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_ab&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 90
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_90&doctype=Standard
-URIDate 2017-03-09

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- Definition

The amount of income tax relating to amounts recognised in other comprehensive income in relation to remeasurements of defined benefit plans. [Refer: Other comprehensive income; Reserve of remeasurements of defined benefit plans; Defined benefit plans [member]]

+ References

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- References

No definition available.

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