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Debt - Additional Information (Detail) - USD ($)
Sep. 30, 2017
Dec. 31, 2016
Debt Instrument [Line Items]    
Revolving credit agreement maximum borrowing capacity $ 600,000,000  
Revolving credit agreement maturity date Jul. 01, 2019  
Borrowings under revolving credit agreement $ 284,700,000 $ 235,294,000
Swingline Subfacility    
Debt Instrument [Line Items]    
Revolving credit agreement maximum borrowing capacity 90,000,000  
Multicurrency borrowing sublimit    
Debt Instrument [Line Items]    
Revolving credit agreement maximum borrowing capacity 75,000,000  
Letter of Credit    
Debt Instrument [Line Items]    
Revolving credit agreement maximum borrowing capacity $ 10,000,000 $ 50,000,000