Average value of new stock issued during the period.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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.

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No definition available.

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- Definition

The cash inflow from the additional capital contribution to the entity.

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-Section 45
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- Definition

The net cash inflow or outflow resulting from the entity's share transaction.

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No definition available.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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Common Stock (Narrative) (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022 CAD ($) $ / shares shares	Dec. 31, 2021 CAD ($) shares	Dec. 31, 2021 $ / shares shares	Aug. 12, 2021 CAD ($)
Debt Instrument [Line Items]
Issuance of common stock \| shares	4,070,000.00	4,990,000
Gross proceeds from Issuance of Common Stock \| $	$ 277	$ 317
Percentage of outstanding stock maximum	10.00%
ATM Program
Debt Instrument [Line Items]
Stock Repurchase Program, Authorized Amount \| $				$ 600
Stock Repurchase Program, Remaining Authorized Repurchase Amount \| $	$ 207
ATM Program \| Common Stock
Debt Instrument [Line Items]
Issuance of common stock \| shares	4,072,469	4,987,123
Gross proceeds from Issuance of Common Stock \| $	$ 250	$ 287
Net proceeds from issuance of common stock \| $	$ 248	$ 284
Average price per share, issued \| (per share)	$ 61.31		$ 57.63
Employee Stock Option Plan
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance \| shares	6,000,000	6,200,000	6,200,000
Share Unit Plans
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance \| shares	2,700,000	3,100,000	3,100,000
Dividend Reinvestment
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance \| shares	10,000,000	14,200,000	14,200,000