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Financial Instruments and Risk Management (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Sep. 27, 2019
Derivative [Line Items] |  |  |  |
Realized loss on interest rate swap | $ 0.1 | $ (0.1) |  |
Amortization of unrealized (gain) loss to interest expense | (0.2) | 0.0 |  |
Unrealized gain (loss) | 0.1 | $ (3.6) |  |
Interest Rate Swap |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative amount |  |  |  | $ 150.0
Unrealized gain on interest rate swap | (0.4) |  |  |
Realized loss on interest rate swap | (0.2) |  |  |
Amortization of unrealized (gain) loss to interest expense | 0.2 |  |  |
Unrealized gain (loss) | 2.3 |  |  |
Prepaid expenses and other current assets |  |  |  |
Derivative [Line Items] |  |  |  |
Cash deposits related to commodity derivative contracts | $ 0.9 |  | $ 0.6 |

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