Aggregate number of common shares reserved for future issuance.

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

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

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Per share or per unit amount of equity securities issued.

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No definition available.

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Number of new stock issued during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Common Stock (Narrative) (Details) - CAD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jul. 11, 2019
Debt Instrument [Line Items]
Issuance of common stock	1,770	450
Gross proceeds from Issuance of Common Stock	$ 203.0	$ 10.0
ATM Program
Debt Instrument [Line Items]
Stock Repurchase Program, Authorized Amount			$ 600.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 500.0
ATM Program \| Common Stock
Debt Instrument [Line Items]
Shares, Issued	1,770
Gross proceeds from Issuance of Common Stock	$ 100.0
Net proceeds from issuance of common stock	$ 98.7
ATM Program \| Average \| Common Stock
Debt Instrument [Line Items]
Shares Issued, Price Per Share	$ 56.56
Employee Stock Option Plan
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	3,900	6,500
Share Unit Plans
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	900	1,000
Dividend Reinvestment
Debt Instrument [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	8,800	12,600