Amount of net income (loss) attributable to preferred shares dividends of noncontrolling interest.

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- Definition

Number of preferred shares that have been repurchased and retired during the period.

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Equity impact of the value of preferred shares that have been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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The percentage points added to the reference rate to compute the variable rate on the preference stock.

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Represents the period in which the dividend rate will reset after the initial period has ended.

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Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity.

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Description of basis of dividend, such as adjustable rate. Excludes percentage rate dividend payments or fixed dollar amounts per share.

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The percentage rate used to calculate dividend payments on preferred stock.

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The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Preferred shares issued by a subsidiary company - (Details) $ in Millions		12 Months Ended
	Dec. 31, 2020 $ / shares shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2014	Dec. 31, 2009 $ / shares shares	Dec. 31, 2007 $ / shares shares
Preferred shares issued by a subsidiary company
Preferred shares repurchased and retired \| $		$ 6.4	$ 8.0
Net income attributable to preferred shares of a subsidiary company \| $		0.7	1.2
Subsidiary Issuer \| Cumulative Preferred Stock
Preferred shares issued by a subsidiary company
Dividend paid \| $		6.8	7.4
Preferred shares repurchased and retired \| $		6.4	8.0
Net income attributable to preferred shares of a subsidiary company \| $		$ 7.4	$ 8.6
Subsidiary Issuer \| Series 1 Shares
Preferred shares issued by a subsidiary company
Number of shares issued in transaction						5,000,000.0
Dividend rate on preferred shares (as a percent)						4.85%
Issuance price per share \| $ / shares						$ 25.00
Preferred Stock, Shares Outstanding	3,465,706
Redemption price after specified date and thereafter (in Canadian dollars per share) \| $ / shares						$ 25.00
Preferred shares repurchased and retired (in shares)		381,794
Subsidiary Issuer \| Series 2 Shares
Preferred shares issued by a subsidiary company
Number of shares issued in transaction					4,000,000.0
Dividend rate on preferred shares (as a percent)			5.74%		7.00%
Issuance price per share \| $ / shares					$ 25.00
Preferred Stock, Shares Outstanding	2,441,766
Redemption price after specified date and thereafter (in Canadian dollars per share) \| $ / shares	$ 25.00
Period for declaration of dividend at reset rate				5 years
Reference rate for dividend				five-year Government of Canada bond yield
Percentage points added to the reference rate				4.18%
Preferred shares repurchased and retired (in shares)		62,365
Subsidiary Issuer \| Series 3 Shares
Preferred shares issued by a subsidiary company
Dividend rate on preferred shares (as a percent)	4.30%
Preferred Stock, Shares Outstanding	957,391
Redemption price after specified date and thereafter (in Canadian dollars per share) \| $ / shares	$ 25.50
Period for declaration of dividend at reset rate		5 years
Reference rate for dividend		90-day Government of Canada Treasury bill rate
Percentage points added to the reference rate	4.18%
Preferred shares repurchased and retired (in shares)		120,000