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Derivatives - Summary of Primary Net Hedging Positions and Corresponding Fair Values (Detail) - Foreign Exchange Forward Contracts [Member] - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
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Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | $ 207.6 | $ 176.2
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | 2.3 | (6.5)
U.S. Dollar/Japanese Yen [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 51.5 | 61.5
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | 0.9 | (1.1)
U.S. Dollar/South Korean Won [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 81.2 | 62.2
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | 1.4 | (3.1)
U.S. Dollar/Euro [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 14.4 | 13.1
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | 0.1 | (0.6)
U.S. Dollar/U.K. Pound Sterling [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 6.9 | 6.1
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net |  | (0.3)
U.S. Dollar/Taiwan Dollar [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 53.6 | 33.3
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | $ (0.1) | $ (1.4)

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