v3.20.2

Equity - Share Repurchase Program (Details) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 30, 2020 USD ($) shares	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) shares	Mar. 25, 2020 USD ($) $ / shares shares
Stock Repurchase Program
Payments for Repurchase of Redeemable Preferred Stock | $				$ 6.4	$ 8.0
Gain (loss) attributable to preferred shares of a subsidiary company | $		$ 1.6	$ 1.7	$ (2.5)	$ (3.1)
Common Stock, Shares, Outstanding		89,222,568		89,222,568		108,675,294
Cumulative Preferred Stock
Stock Repurchase Program
Shares repurchased and canceled | $				$ 6.4
Series 1 Shares
Stock Repurchase Program
Shares repurchased and canceled (in shares)				381,794
Series 2 Shares
Stock Repurchase Program
Shares repurchased and canceled (in shares)				62,365
Series 3 Shares
Stock Repurchase Program
Shares repurchased and canceled (in shares)				120,000
NCIB
Stock Repurchase Program
Public float amount used to determine share amount, percent						10.00%
Shares repurchased and canceled (in shares)				7,540,105
Shares repurchased and canceled | $				$ 15.8
Gain (loss) attributable to preferred shares of a subsidiary company | $				$ (7.4)
NCIB | Series 1 Shares
Stock Repurchase Program
Number of shares authorized for repurchase						384,750
Dividend percent of cumulative redeemable preferred shares				4.85
NCIB | Series 2 Shares
Stock Repurchase Program
Number of shares authorized for repurchase						223,072
Dividend percent of cumulative redeemable preferred shares				7.0
NCIB | Series 3 Shares
Stock Repurchase Program
Number of shares authorized for repurchase						133,031
SIB
Stock Repurchase Program
Number of shares authorized for repurchase							12,820,512
Shares repurchased and canceled (in shares)	12,500,000
Shares repurchased and canceled | $	$ 25.8
Share repurchase authorized amount | $							$ 25.0
Number of share repurchase authorized as percentage of common stock issued and outstanding							12.00%
Share purchase price increment | $ / shares							$ 0.05
Minimum | SIB
Stock Repurchase Program
Share purchase price | $ / shares							1.95
Maximum | NCIB
Stock Repurchase Program
Number of shares authorized for repurchase						10,578,799
Stock Repurchase Program Number Of Shares Authorized To Be Repurchased Per Day						9,243
Maximum | SIB
Stock Repurchase Program
Share purchase price | $ / shares							$ 2.20
Series E Debentures | NCIB
Stock Repurchase Program
Share repurchase authorized amount | $						$ 11.5

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The public float percentage used to determine common shares purchased as part of an Normal Course Issuer Bid.

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The number of shares authorized to be repurchased per day by an entity's Board of Directors under the stock repurchase plan.

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