v3.20.1

Equity - Share Repurchase Program (Details) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($) shares	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) shares	May 06, 2020 shares	Mar. 25, 2020 USD ($) $ / shares shares
Stock Repurchase Program
Payments for Repurchase of Redeemable Preferred Stock | $		$ 6.4	$ 7.7
Gain (loss) attributable to preferred shares of a subsidiary company | $		$ (5.8)	$ (6.5)
Common Stock, Shares, Outstanding		105,502,338		108,675,294	93,002,338
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
Shares repurchased and canceled | $		$ 6.4
NCIB
Stock Repurchase Program
Public float amount used to determine share amount, percent				10.00%
Shares repurchased and canceled (in shares)		3,760,335
Shares repurchased and canceled | $		$ 8.2
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
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
SIB | Subsequent event
Stock Repurchase Program
Shares repurchased and canceled (in shares)	1,250,000
Shares repurchased and canceled | $	$ 25.0
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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