v3.7.0.1
Derivative Instruments - Fair Values of Outstanding Derivative Instruments (Detail) - USD ($)
$ in Thousands
Apr. 30, 2017
Jan. 31, 2017
Derivatives, Fair Value [Line Items]    
Derivative Assets $ 6,934  
Derivative Liabilities 4,229  
Forward Contracts | Designated as Hedging Instrument | Prepaid expenses and other current assets and Other assets    
Derivatives, Fair Value [Line Items]    
Derivative Assets 5,882 $ 7,149
Forward Contracts | Designated as Hedging Instrument | Accrued expenses and other current liabilities and Other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative Liabilities 3,728 1,605
Forward Contracts | Not Designated as Hedging Instrument | Prepaid expenses and other current assets    
Derivatives, Fair Value [Line Items]    
Derivative Assets 1,052 760
Forward Contracts | Not Designated as Hedging Instrument | Accrued expenses and other current liabilities    
Derivatives, Fair Value [Line Items]    
Derivative Liabilities $ 501 $ 522