Debt - Schedule of Maturities of Company's Debt (Details) - USD ($) $ in Millions	Jun. 28, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020	$ 0.0
2021	25.0
2022	16.3
2023	25.0
2024	0.0
2025	0.0
Thereafter	25.0
Total	91.3
Loan Notes \| 3.67% Loan Notes due 2021
Debt Instrument [Line Items]
2020	0.0
2021	25.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
Thereafter	0.0
Total	25.0	$ 25.0
Loan Notes \| 4.88% Loan Notes due 2023
Debt Instrument [Line Items]
2020	0.0
2021	0.0
2022	0.0
2023	25.0
2024	0.0
2025	0.0
Thereafter	0.0
Total	25.0	25.0
Loan Notes \| 4.94% Loan Notes due 2026
Debt Instrument [Line Items]
2020	0.0
2021	0.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
Thereafter	25.0
Total	25.0	25.0
Revolving credit facility
Debt Instrument [Line Items]
2020	0.0
2021	0.0
2022	16.3
2023	0.0
2024	0.0
2025	0.0
Thereafter	0.0
Total	$ 16.3	$ 17.5

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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