General - Stock Compensation - Stock Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock Compensation
Stock compensation expense	$ 7.0	$ 5.4	$ 13.0	$ 15.0
Stock Compensation Expense Discontinued Operations	$ 0.4	$ 0.2	$ 0.6	$ 0.4
Minimum
Stock Compensation
Estimated forfeitures (as a percent)	0.00%	0.00%	0.00%	0.00%
Maximum
Stock Compensation
Estimated forfeitures (as a percent)	4.00%	4.00%	4.00%	4.00%