Derivatives Instruments (Credit Risk) (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 CAD ($) Days	Dec. 31, 2022 CAD ($)
Credit Derivatives [Line Items]
Total cash deposits/collateral on hand	$ 101	$ 224
Financial Asset, Past Due [Member]
Credit Derivatives [Line Items]
Financial assets, considered to be past due	142	131
Credit Concentration Risk
Credit Derivatives [Line Items]
Concentration Risk, maximum exposure	1,200	1,900
Total cash deposits/collateral on hand	310	386
Credit Concentration Risk \| Receivables, net
Credit Derivatives [Line Items]
Fair Value, Financial assets, considered to be past due	$ 127	$ 114
Average number of days financial asset outstanding \| Days	64

The average number of days outstanding for financial assets, considered o be past due.

No definition available.

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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

+ References

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- Definition

Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

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- Definition

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

+ References

No definition available.

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- Definition

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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- Definition

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

+ References

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