The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities]

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The gains (losses) on the ineffective portion of cash flow hedges recognised in profit or loss. [Refer: Cash flow hedges [member]]

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The amount of reclassification adjustments related to cash flow hedges, before tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Cash flow hedges [member]; Other comprehensive income]

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The amount of instruments sold with the intent to reacquire in repurchase agreements and cash collateral on securities lent.

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Assets Sold Under Agreements To Repurchase, Interest Rate1

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Assets Sold Under Agreements To Repurchase, Maturity Period

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[Line Items] For Disclosure Of Fair Value Measurement Of Assets And Liabilities [Table]

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Discount Rate, Significant Unobservable Inputs, Assets

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Financial Forecast Of Cash Flows For Cash-Generating Unit, Significant Unobservable Inputs, Assets, Per Square Foot

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Growth Rate, Significant Unobservable Inputs, Assets

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Long-Term Vacancy Rate, Significant Unobservable Inputs, Assets

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Property, Plant and Equipment Expected Return Period, Significant Unobservable Inputs, Assets

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Risk-Adjusted Spread, Significant Unobservable Inputs, Assets

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Terminal Capitalization Rate, Significant Unobservable Inputs, Assets

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Total Invested Assets and Related Net Investment Income - Narrative (Details)	12 Months Ended
	Dec. 31, 2019 CAD ($)	Dec. 31, 2018 CAD ($) square_foot $ / square_foot	Dec. 31, 2017 CAD ($)
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Derivative liabilities		$ 2,295,000,000	$ 1,756,000,000
Net ineffectiveness on fair value hedges		1,000,000	3,000,000
Financial assets		$ 143,061,000,000	$ 137,691,000,000
Repurchase agreement interest rate		1.92%	1.25%
Financial assets, at fair value		$ 144,673,000,000	$ 140,292,000,000
Carrying value of securities lent		1,824,000,000	1,976,000,000
Mortgages and loans
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		46,822,000,000	42,805,000,000
Financial assets, at fair value		48,434,000,000	45,406,000,000
Asset-backed securities
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		$ 7,366,000,000	5,899,000,000
Mortgages \| Level 3
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Risk-adjusted spreads		20 years
Asset-Backed Securities In Principal Reinvestment Account
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		$ 124,000,000	75,000,000
Financial assets \| Level 3
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		7,704,000,000	6,805,000,000
Securitized mortgages
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		1,328,000,000	1,283,000,000
Financial assets, at fair value		1,318,000,000	1,267,000,000
Cash And Cash Equivalents In Principal Reinvestment Account
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		0	0
Transferred Assets
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets, at fair value		1,824,000,000	1,976,000,000
Securities lending
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Carrying value of securities lent		2,217,000,000	1,467,000,000
Collateral associated with securities lending
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Carrying value of securities lent		$ 2,338,000,000	1,546,000,000
Loans \| Level 3
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Risk-adjusted spreads		10 years
Bottom of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Repurchase agreement maturity period		7 days
Top of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Repurchase agreement maturity period		365 days
Weighted average
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Repurchase agreement maturity period		127 days
Securitized mortgages
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial liabilities		$ 1,453,000,000	1,355,000,000
Financial liabilities, at fair value		1,446,000,000	1,346,000,000
Fair value through profit or loss \| Asset-backed securities
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		4,527,000,000	3,681,000,000
Fair value through profit or loss \| Financial assets \| Level 2
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Financial assets		40,730,000,000	38,601,000,000
Measured at fair value
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Derivative liabilities		$ 2,295,000,000	$ 1,756,000,000
Discounted cash flow \| Bottom of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Rental growth rate (per annum)		0.00%
Long-term vacancy rate		2.00%
Discount rate		4.00%
Terminal capitalization rate		4.25%
Discounted cash flow \| Top of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Rental growth rate (per annum)		3.00%
Long-term vacancy rate		10.00%
Discount rate		10.30%
Terminal capitalization rate		8.75%
Discounted cash flow \| Retail and office properties \| Bottom of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Estimated rental value (per square foot, per annum) \| square_foot		12
Discounted cash flow \| Retail and office properties \| Top of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Estimated rental value (per square foot, per annum) \| $ / square_foot		76
Discounted cash flow \| Industrial properties \| Bottom of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Estimated rental value (per square foot, per annum) \| $ / square_foot		3,000,000
Discounted cash flow \| Industrial properties \| Top of range
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Estimated rental value (per square foot, per annum) \| $ / square_foot		11,000,000
Discounted cash flow \| Investment property
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Expected return period		10 years
Scenario, Forecast
Disclosure Of Fair Value Measurement of Assets and Liabilities [Line Items]
Reclassification adjustments on cash flow hedges, before tax	$ 2,000,000