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Derivative Financial Instruments and Hedging Activities (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) Subsidiary Contract | Dec. 31, 2019 USD ($) Contract | Dec. 31, 2018 USD ($) | Jul. 01, 2018 USD ($) | Jul. 03, 2016 USD ($)
Derivative, Fair Value [Abstract] |  |  |  |  |
(Gains) losses in other non-operating income (deductions) | $ 5.3 | $ 8.2 | $ 1.5 |  |
Minimum [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Number of foreign subsidiaries in which portion of net investment is hedged | Subsidiary | 1 |  |  |  |
Foreign Exchange Forward [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Number of contracts | Contract | 0 | 0 |  |  |
(Gains) losses in other non-operating income (deductions) | $ 0.2 | $ 2.1 | $ (0.7) |  |
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount |  |  |  | $ 150.0 |
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Non-Current Liabilities [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative liability | 7.7 |  |  |  |
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount | 29.0 |  |  |  | $ 300.0
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Current Liabilities [Member] | Maximum [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative liability | 0.1 |  |  |  |
Net Investment Hedge [Member] | Designated as Hedging Instrument [Member] | Cross Currency Rate Swap [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Notional amount |  |  |  | $ 150.0 |
Net Investment Hedge [Member] | Designated as Hedging Instrument [Member] | Cross Currency Rate Swap [Member] | Other Assets and Deferred Charges [Member] |  |  |  |  |
Derivative, Fair Value [Abstract] |  |  |  |  |
Fair value of derivative asset | $ 0.4 |  |  |  |

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