Pension Plans - Fair Value of Pension Plan Assets (Details) - Pension Plan - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 68.0	$ 64.0
Total assets at fair value	255.0	253.7
Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3.7	5.4
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	64.3	58.6
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Cash and equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3.7	5.4
Cash and equivalents | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3.7	5.4
Cash and equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Cash and equivalents | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32.6	30.8
Mutual funds | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Mutual funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32.6	30.8
Mutual funds | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Mutual funds | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure [Line Items]
Investments measured at NAV	125.6	155.1
Real estate funds | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure [Line Items]
Investments measured at NAV	18.7	15.2
Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31.7	27.8
Insurance contracts | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31.7	27.8
Insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Other private investments | Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure [Line Items]
Investments measured at NAV	$ 42.7	$ 19.4