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Derivatives - Summary of Primary Net Hedging Positions and Corresponding Fair Values (Detail) - Foreign Exchange Forward Contracts [Member] - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | $ 176.2 | $ 154.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | (6.5) | (0.2)
U.S. Dollar/Japanese Yen [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 61.5 | 45.9
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | (1.1) |
U.S. Dollar/South Korean Won [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 62.2 | 51.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | (3.1) | 0.2
U.S. Dollar/Euro [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 13.1 | 15.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | (0.6) | 0.2
U.S. Dollar/U.K. Pound Sterling [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 6.1 | 8.3
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | (0.3) | (0.2)
U.S. Dollar/Taiwan Dollar [Member] |  |
Derivative [Line Items] |  |
Currency Hedged (Buy/Sell), Gross Notional Value, Net | 33.3 | 33.1
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net | $ (1.4) | $ (0.4)

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