PURCHASED INTANGIBLE ASSETS - Goodwill and Finite Lived Intangible Assets (Details) - USD ($)
$ in Thousands
 3 Months Ended
Apr. 30, 2017
Jan. 31, 2017
Apr. 30, 2016
Finite-Lived Intangible Assets      
Intangible Assets, Gross Amount $ 11,612    
Accumulated amortization 3,614    
Intangible Assets - Net Amount 7,998 $ 8,181  
Indefinite-Lived Intangible Assets      
Goodwill 34,913 34,913 $ 36,813
GPS      
Indefinite-Lived Intangible Assets      
Goodwill 18,500 18,500  
TRC      
Indefinite-Lived Intangible Assets      
Goodwill 14,400 14,400  
APC      
Indefinite-Lived Intangible Assets      
Goodwill $ 2,000 2,000  
Trade Name | GPS/TRC      
Finite-Lived Intangible Assets      
Finite-Lived Intangible Assets - Estimated Useful Life 15 years    
Finite Lived Intangible Assets - Gross Amount $ 8,142    
Accumulated amortization 2,875    
Finite Lived Intangible Assets - Net Amount $ 5,267 5,328  
Process certifications | TRC      
Finite-Lived Intangible Assets      
Finite-Lived Intangible Assets - Estimated Useful Life 7 years    
Finite Lived Intangible Assets - Gross Amount $ 1,897    
Accumulated amortization 384    
Finite Lived Intangible Assets - Net Amount 1,513 1,581  
Customer Relationships | TRC/APC      
Finite-Lived Intangible Assets      
Finite Lived Intangible Assets - Gross Amount 1,346    
Accumulated amortization 323    
Finite Lived Intangible Assets - Net Amount $ 1,023 1,072  
Customer Relationships | TRC/APC | Minimum      
Finite-Lived Intangible Assets      
Finite-Lived Intangible Assets - Estimated Useful Life 4 years    
Customer Relationships | TRC/APC | Maximum      
Finite-Lived Intangible Assets      
Finite-Lived Intangible Assets - Estimated Useful Life 10 years    
Other intangibles      
Finite-Lived Intangible Assets      
Finite Lived Intangible Assets - Gross Amount $ 46    
Accumulated amortization 32    
Finite Lived Intangible Assets - Net Amount $ 14 $ 19