Insurance Contract Liabilities and Investment Contract Liabilities - Gross Claims and Benefits Paid (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Insurance Contracts [Abstract]
Maturities and surrenders	$ 3,205	$ 2,993
Annuity payments	2,017	1,979
Death and disability benefits	4,876	4,594
Health benefits	7,246	6,913
Policyholder dividends and interest on claims and deposits	1,378	1,828
Total gross claims and benefits paid	$ 18,722	$ 18,307

Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held

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Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held, Annuity Payments

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Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held, Death And Disability Benefits

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Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held, Health Benefits

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Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held, Maturities And Surrenders

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Expense For Policyholder Claims And Benefits Paid, Without Reduction For Reinsurance Held, Policyholder Dividends And Interest On Claims And Deposits

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Insurance Contracts [Abstract]

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