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Pension and Other Post-Employment Plans - Additional Information (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Number of company sponsored defined benefit pension plans | 2 |  |  |
Cost of defined contribution pension plans | $ 7.7 |  | $ 7.9 | $ 7.2
Deferred compensation liability | 13.8 |  | 11.1 |
Other Expense |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Withdrawal charge | 2.3 |  |  |
U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Amendments | $ 0.0 |  | $ 0.0 |
Weighted-average target return of pension plans | 7.40% |  | 7.00% | 7.00%
Expected contribution to defined benefit plan | $ 4.3 |  |  |
Non-U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Amendments | $ 0.2 | [1] | $ 0.0 | $ 2.6
Weighted-average target return of pension plans | 3.60% |  | 4.20% | 4.20%
Expected amortization of actuarial loss in next fiscal year | $ 4.6 |  |  |
Expected amortization of prior service cost in next fiscal year | 0.1 |  |  |
Expected contribution to defined benefit plan | $ 1.4 |  |  |
Maximum | Equity Securities | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 69.00% |  |  |
Maximum | Equity Securities | Non-U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 35.00% |  |  |
Maximum | Fixed Income Securities | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 44.00% |  |  |
Maximum | Cash and cash equivalents | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 20.00% |  |  |
Maximum | Debt Securities | Non-U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 75.00% |  |  |
Minimum | Equity Securities | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 54.00% |  |  |
Minimum | Equity Securities | Non-U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 25.00% |  |  |
Minimum | Fixed Income Securities | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 29.00% |  |  |
Minimum | Cash and cash equivalents | U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 0.00% |  |  |
Minimum | Debt Securities | Non-U.S. Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Target asset allocation | 65.00% |  |  |
[1] | While the non-U.S. benefit plan has not yet been amended, this component of the change to the benefit obligation of the non-U.S. benefit plan during the year ended December 31, 2020 represents the estimated incremental impact of the November 2020 U.K. High Court ruling, as described above.

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