Derivatives - Summary of Primary Net Hedging Positions and Corresponding Fair Values (Detail) - Forward Exchange Contracts [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	$ 158.9	$ 154.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(2.1)	(0.2)
U.S. Dollar/Japanese Yen [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	55.2	45.9
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(0.4)
U.S. Dollar/South Korean Won [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	40.9	51.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(0.4)	0.2
U.S. Dollar/Euro [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	13.6	15.7
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(0.3)	0.2
U.S. Dollar/U.K. Pound Sterling [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	6.2	8.3
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(0.1)	(0.2)
U.S. Dollar/Taiwan Dollar [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	43.0	33.1
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	$ (0.9)	$ (0.4)