Consolidated Statements of Shareholders' Equity - USD ($) $ in Millions	Total	Common shares	Additional paid-in surplus	Retained earnings	Accumulated other comprehensive (loss)	Parent	Non-controlling interests	Cumulative effect, period of adoption Retained earnings	Adjusted balance Retained earnings
Beginning balance at Dec. 31, 2018		$ 1.2	$ 1,089.1	$ 816.6	$ (202.4)				$ 816.6
Changes in common shareholders' equity
Share-based compensation			7.9
Net (loss) income	$ 104.7			104.7
Loss (income) attributable to non-controlling interests	(1.6)			(1.6)
Change in carrying value of Series B preference shares				(3.9)
Net change in foreign currency translation	(69.0)				(69.0)
Ending balance at Sep. 30, 2019	1,746.0		1,097.0	915.8	(271.4)	$ 1,742.6	$ 3.4
Beginning balance at Jun. 30, 2019		1.2	1,093.5	918.5	(229.1)				918.5
Changes in common shareholders' equity
Share-based compensation			3.4
Other, net			0.1
Net (loss) income	(7.6)			(7.6)
Loss (income) attributable to non-controlling interests	(0.4)			(0.4)
Change in carrying value of Series B preference shares				5.3
Net change in foreign currency translation	(42.3)				(42.3)
Ending balance at Sep. 30, 2019	1,746.0		1,097.0	915.8	(271.4)	1,742.6	3.4
Beginning balance at Dec. 31, 2019	1,642.8	1.2	1,098.2	778.5	(237.5)			$ (6.8)	771.7
Changes in common shareholders' equity
Share-based compensation			1.7
Net (loss) income	(232.5)			(232.5)
Loss (income) attributable to non-controlling interests	(0.2)			(0.2)
Change in carrying value of Series B preference shares				25.5
Net change in foreign currency translation	31.1				31.1
Ending balance at Sep. 30, 2020	1,461.0		1,099.9	564.5	(206.4)	1,459.2	1.8
Beginning balance at Jun. 30, 2020		$ 1.2	1,102.4	660.0	(243.9)				$ 660.0
Changes in common shareholders' equity
Share-based compensation			(2.5)
Net (loss) income	(104.0)			(104.0)
Loss (income) attributable to non-controlling interests	(0.2)			(0.2)
Change in carrying value of Series B preference shares				8.7
Net change in foreign currency translation	37.5				37.5
Ending balance at Sep. 30, 2020	$ 1,461.0		$ 1,099.9	$ 564.5	$ (206.4)	$ 1,459.2	$ 1.8