Other Current and Non-Current Liabilities - Components of Other Current and Other Non-Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Other current liabilities:
Accrued salaries, wages and related costs	$ 209.2	$ 191.5
Accrued operating expenses	192.1	197.2
Accrued customer volume rebates	83.3	78.3
Accrued interest	37.8	41.6
Accrued employee benefit liability	4.9	5.5
Total	527.3	514.1
Other non-current liabilities:
Accrued employee benefit liability	201.0	178.5
Other postretirement liability	38.3	38.2
Uncertain tax position liability	381.4	384.0
Other various liabilities	107.6	129.5
Total	$ 728.3	$ 730.2