Pension Benefits and Postretirement Benefits Other Than Pensions - Pension Income (Details) - Pension Plans - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Interest Cost on Projected Benefit Obligation	$ 1.7	$ 4.5	$ 3.5	$ 9.0
Expected Return on Plan Assets	(2.4)	(7.4)	(4.7)	(14.7)
Amortization of Net Actuarial Loss	0.8	1.5	1.5	3.0
Total Pension (Benefit) Expense	$ 0.1	$ (1.4)	$ 0.3	$ (2.7)