Total Equity - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended		9 Months Ended
	Sep. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Retained Earnings
Summary Of Changes In Equity [Line Items]
Acquisition and Surrender of Common Shares	$ 1.4	$ 34.1	$ 27.2	$ 34.1	$ 28.6