Changes in Fair Value of Level 3 Assets (Detail) (CAD) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Mortgage Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value at beginning	1	1
Net purchases/(sales)	(1)
Fair value at ending		1
Venture Capital
Defined Benefit Plan Disclosure [Line Items]
Fair value at beginning	188	158
Net realized gains/(losses)	(16)	(17)
Net unrealized gains/(losses)	40	44
Net purchases/(sales)	(1)	3
Fair value at ending	211	188

Fair value measurement with unobservable inputs net realized gains losses.

No definition available.

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- Definition

Fair value measurement with unobservable inputs net unrealized gains losses.

+ References

No definition available.

+ Details

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph c

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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