Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Additional Information (Detail)

v3.10.0.1
Basis of Presentation (Additional Information (Detail)
9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Toshiba Japan [Member]    
Basis Of Presentation [Line Items]    
Engineering Revenues Percentage 67.00% 98.00%
Toshiba Japan [Member] | Sales Revenue, Net [Member]    
Basis Of Presentation [Line Items]    
Concentration Risk, Percentage 27.00% 24.00%
Toshiba Japan [Member] | Accounts Receivable [Member]    
Basis Of Presentation [Line Items]    
Concentration Risk, Percentage 1.00% 0.00%
Toshiba Japan [Member] | Accrued Project Revenue [Member]    
Basis Of Presentation [Line Items]    
Concentration Risk, Percentage 0.00% 59.00%
AMA SA [Member] | Sales Revenue, Net [Member]    
Basis Of Presentation [Line Items]    
Concentration Risk, Percentage 14.00% 8.00%
AMA SA [Member] | Accounts Receivable [Member]    
Basis Of Presentation [Line Items]    
Concentration Risk, Percentage 0.00% 6.00%