Senior Debentures and Innovative Capital Instruments - Senior Debentures (Details) - CAD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Senior Debentures
Disclosure of detailed information about borrowings [line items]
Fair value of borrowings outstanding	$ 215	$ 271
Sun Life Assurance Series B Senior Debentures Issued June 25, 2002
Disclosure of detailed information about borrowings [line items]
Interest rate	7.09%
Borrowings outstanding	$ 200	$ 200
Government of Canada Bond Yield \| Sun Life Assurance Series B Senior Debentures Issued June 25, 2002
Disclosure of detailed information about borrowings [line items]
Adjustment to interest rate basis	0.32%

The amount of outstanding funds that the entity is obligated to repay.

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

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Borrowings, At Fair Value

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