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Pension and Other Post-Employment Plans - Summary of Pension Assets in Three-Tier Fair Value Hierarchy for Benefit Plan (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Receivables |  | $ 200,000 | $ 200,000 |
U.S. Benefit Plan |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 142,500,000 | 131,600,000 | $ 118,800,000
U.S. Benefit Plan | Total |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value | [1] | 142,300,000 | 131,400,000 |
U.S. Benefit Plan | Total | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,400,000 | 4,000,000.0 |
U.S. Benefit Plan | Total | US Large Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 36,300,000 | 46,100,000 |
U.S. Benefit Plan | Total | US Small and Mid Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 24,600,000 | 23,800,000 |
U.S. Benefit Plan | Total | Developed international |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 19,700,000 | 13,000,000.0 |
U.S. Benefit Plan | Total | Emerging markets |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 11,900,000 | 10,700,000 |
U.S. Benefit Plan | Total | Real estate |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 400,000 | 400,000 |
U.S. Benefit Plan | Level 1 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 95,500,000 | 102,100,000 |
U.S. Benefit Plan | Level 1 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,400,000 | 4,000,000.0 |
U.S. Benefit Plan | Level 1 | US Large Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 36,300,000 | 46,100,000 |
U.S. Benefit Plan | Level 1 | US Small and Mid Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 24,600,000 | 23,800,000 |
U.S. Benefit Plan | Level 1 | Developed international |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 10,200,000 | 7,100,000 |
U.S. Benefit Plan | Level 1 | Emerging markets |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 9,700,000 | 10,200,000 |
U.S. Benefit Plan | Level 1 | Real estate |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 400,000 | 400,000 |
U.S. Benefit Plan | Level 2 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 46,800,000 | 29,300,000 |
U.S. Benefit Plan | Level 2 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 2 | US Large Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 2 | US Small and Mid Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 2 | Developed international |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 9,500,000 | 5,900,000 |
U.S. Benefit Plan | Level 2 | Emerging markets |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 2,200,000 | 500,000 |
U.S. Benefit Plan | Level 2 | Real estate |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | US Large Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | US Small and Mid Cap |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | Developed international |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | Emerging markets |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
U.S. Benefit Plan | Level 3 | Real estate |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 57,400,000 | 55,200,000 | $ 47,700,000
Non-U.S. Benefit Plan | Total |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 57,400,000 | 55,200,000 |
Non-U.S. Benefit Plan | Total | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 7,400,000 | 200,000 |
Non-U.S. Benefit Plan | Total | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 3,800,000 |
Non-U.S. Benefit Plan | Total | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value | [2] | 29,600,000 | 40,700,000 |
Non-U.S. Benefit Plan | Total | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 15,900,000 | 10,500,000 |
Non-U.S. Benefit Plan | Total | Insurance-linked securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,500,000 | 0 |
Non-U.S. Benefit Plan | Level 1 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 400,000 | 11,200,000 |
Non-U.S. Benefit Plan | Level 1 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 400,000 | 200,000 |
Non-U.S. Benefit Plan | Level 1 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 3,800,000 |
Non-U.S. Benefit Plan | Level 1 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value | [2] | 0 | 0 |
Non-U.S. Benefit Plan | Level 1 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 7,200,000 |
Non-U.S. Benefit Plan | Level 1 | Insurance-linked securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 2 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 52,500,000 | 44,000,000.0 |
Non-U.S. Benefit Plan | Level 2 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 7,000,000.0 | 0 |
Non-U.S. Benefit Plan | Level 2 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 2 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value | [2] | 29,600,000 | 40,700,000 |
Non-U.S. Benefit Plan | Level 2 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 15,900,000 | 3,300,000 |
Non-U.S. Benefit Plan | Level 2 | Insurance-linked securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 3 |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,500,000 | 0 |
Non-U.S. Benefit Plan | Level 3 | Cash and cash equivalents |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 3 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 3 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value | [2] | 0 | 0 |
Non-U.S. Benefit Plan | Level 3 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Non-U.S. Benefit Plan | Level 3 | Insurance-linked securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,500,000 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Total | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,900,000 | 10,500,000 |
Fixed Income Securities | U.S. Benefit Plan | Total | Asset-backed securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 3,800,000 | 13,500,000 |
Fixed Income Securities | U.S. Benefit Plan | Total | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 31,300,000 | 9,400,000 |
Fixed Income Securities | U.S. Benefit Plan | Total | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 5,000,000.0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 1 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 4,900,000 | 10,500,000 |
Fixed Income Securities | U.S. Benefit Plan | Level 1 | Asset-backed securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 1 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 1 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 5,000,000.0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 2 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 2 | Asset-backed securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 3,800,000 | 13,500,000 |
Fixed Income Securities | U.S. Benefit Plan | Level 2 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 31,300,000 | 9,400,000 |
Fixed Income Securities | U.S. Benefit Plan | Level 2 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 3 | Government securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 3 | Asset-backed securities |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 3 | Corporate bonds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | 0 | 0 |
Fixed Income Securities | U.S. Benefit Plan | Level 3 | Diversified investment funds |  |  |  |
Fair Value Hierarchy Of Plan Assets By Category [Line Items] |  |  |  |
Total assets at fair value |  | $ 0 | $ 0 |
[1] | Total assets at fair value in the table above exclude a net receivable of $0.2 million at December 31, 2020 and 2019, respectively.
[2] | These funds primarily invest in a diversified portfolio of equity securities and fixed income securities.

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