Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities - Additional Information (Detail)

v3.10.0.1
Derivative Instruments and Hedging Activities - Additional Information (Detail) - USD ($)
$ in Millions
9 Months Ended 12 Months Ended
Sep. 30, 2018
Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative asset fair value $ 1.6 $ 5.8
Derivative liability fair value 3.9 6.6
Cash flow hedges reclassified into earnings over next twelve months 0.8  
Foreign exchange currency contracts [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative aggregate notional amounts 306.4  
Derivative asset fair value 1.6 5.8
Derivative liability fair value 3.9 6.6
Foreign exchange currency contracts [Member] | Derivatives designated as cash flow hedging instruments [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative aggregate notional amounts 61.1 104.9
Derivative asset fair value 0.7 2.9
Derivative liability fair value $ 2.0 $ 4.0
Freestanding derivatives [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative average remaining maturity period 1 month 1 month
Maximum [Member] | Foreign exchange currency contracts [Member] | Derivatives designated as cash flow hedging instruments [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative maximum remaining maturity period 12 months  
Maximum [Member] | Foreign exchange forward contracts [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Derivative maximum remaining maturity period 12 months 12 months