Total Invested Assets and Related Net Investment Income - Changes in Asset Fair Value and Currency Change (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	$ (4,376)	$ 2,780
Fair value changes on investment properties	529	211
Foreign exchange gains (losses)	446	(388)
Fair value and foreign currency changes on assets and liabilities	(3,373)	2,603
Gain on sale of operating lease	28
Cash, cash equivalents and short-term securities
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	8	1
Debt securities
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	(2,704)	1,630
Equity securities
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	(401)	441
Derivative assets
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	(1,295)	649
Other invested assets
Disclosure of fair value measurement of assets [line items]
Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets	$ 16	$ 59

The increase (decrease) in the fair value of a financial asset (or group of financial assets) designated as measured at fair value through profit or loss that is attributable to changes in the credit risk of that asset determined either: (a) as the amount of change in its fair value that is not attributable to changes in market conditions that give rise to market risk ; or (b) using an alternative method the entity believes more faithfully represents the amount of change in its fair value that is attributable to changes in the credit risk of the asset. [Refer: Credit risk [member]; Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 9
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_9_c&doctype=Standard
-URIDate 2017-03-09

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Section A Statement of cash flows for an entity other than a financial institution
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2017-03-09

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The gains (losses) recognised in profit or loss for assets measured at fair value that are attributable to the change in unrealised gains or losses relating to those assets held at the end of the reporting period. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2017-01-01
-Paragraph 93
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2017-03-01&anchor=para_93_f&doctype=Standard
-URIDate 2017-03-09

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