Financial Instruments - Fair Value on a Recurring Basis (Details) - Fair value measured on a recurring basis - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Assets
Plan assets for deferred compensation	$ 2.5	$ 2.5
Total assets	2.5	3.7
Liabilities
Plan liabilities for deferred compensation	2.5	2.5
Derivative liabilities	0.1	0.2
Contingent Consideration	3.2
Total liabilities	6.4	2.7
Interest Rate Swaps
Assets
Derivative outstanding		1.2
Liabilities
Derivative liabilities	0.6
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Plan assets for deferred compensation	2.5	2.5
Total assets	2.5	2.5
Liabilities
Plan liabilities for deferred compensation	2.5	2.5
Total liabilities	2.5	2.5
Significant Other Observable Inputs (Level 2)
Assets
Total assets		1.2
Liabilities
Derivative liabilities	0.1	0.2
Total liabilities	0.7	0.2
Significant Other Observable Inputs (Level 2) | Interest Rate Swaps
Assets
Derivative outstanding		$ 1.2
Liabilities
Derivative liabilities	0.6
Significant Unobservable Inputs (Level 3)
Liabilities
Contingent Consideration	3.2
Total liabilities	$ 3.2