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Financial Derivatives and Hedging Activities - Narrative (Detail) $ in Millions | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2021 EUR (€) | Oct. 31, 2019 EUR (€)
Derivative [Line Items] |  |  |  |
Pre-tax gain from changes in currency exchange rates | $ | $ (9.7) | $ 13.8 |  |
Term Loans |  |  |  |
Derivative [Line Items] |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | € 220,000,000 |
Floating-to-fixed Interest Rate Swap Agreement |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative notional amount |  |  |  | € 180,000,000
Derivative fixed interest rate |  |  |  | 0.0395%
Loans variable rate of interest |  |  |  | € 180,000,000
Minimum |  |  |  |
Derivative [Line Items] |  |  |  |
Long-term debt percentage bearing fixed Interest rate |  |  |  | 0.00%
Minimum | Fair Value, Measurements |  |  |  |
Derivative [Line Items] |  |  |  |
Accumulated other comprehensive income realization period | 12 months |  |  |
Maximum | Fair Value, Measurements |  |  |  |
Derivative [Line Items] |  |  |  |
Accumulated other comprehensive income realization period | 18 months |  |  |
Designated as Hedging | Cash Flow Hedges | Minimum |  |  |  |
Derivative [Line Items] |  |  |  |
Maturities of foreign currency derivative contracts | 1 month |  |  |
Designated as Hedging | Cash Flow Hedges | Maximum |  |  |  |
Derivative [Line Items] |  |  |  |
Maturities of foreign currency derivative contracts | 18 months |  |  |
Not Designated as Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Maturities of foreign currency derivative contracts | 1 month |  |  |

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