Quarterly report pursuant to Section 13 or 15(d)

Goodwill and Intangible Assets - Additional Information (Detail)

v3.7.0.1
Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)
 1 Months Ended
Jan. 31, 2017
Jul. 31, 2017
Aug. 01, 2016
Jul. 31, 2016
May 05, 2016
Goodwill And Intangible Assets [Line Items]          
Goodwill $ 23,287,000 $ 24,668,000      
DCC Labs [Member]          
Goodwill And Intangible Assets [Line Items]          
Goodwill     $ 45,800,000   $ 7,255,000
Fair value of reporting unit less than carrying value     102,500,000    
Estimated implied fair value     $ 22,300,000    
Loss on impairment of long-lived assets $ 23,500,000        
DCC Labs [Member] | Minimum [Member]          
Goodwill And Intangible Assets [Line Items]          
Excess fair value amount over and above the carrying value of the net assets       $ 15,400,000  
Excess fair value percentage over and above the carrying value of the net assets       15.00%  
DCC Labs [Member] | Maximum [Member]          
Goodwill And Intangible Assets [Line Items]          
Excess fair value amount over and above the carrying value of the net assets       $ 25,000,000  
Excess fair value percentage over and above the carrying value of the net assets       24.40%