PURCHASED INTANGIBLE ASSETS - Goodwill and Finite Lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jul. 31, 2019	Apr. 30, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018	Jan. 31, 2019
Finite-Lived Intangible Assets
Intangible Assets - Gross Carrying Amount	$ 11,566			$ 11,566
Accumulated Amortization	6,021			6,021
Other intangible assets, net	5,545			5,545		$ 6,137
Amortization of purchased intangible assets	293		$ 253	592	$ 506
Indefinite-Lived Intangible Assets
Goodwill	30,766		$ 34,329	30,766	$ 34,329	32,838
Impairment loss				2,072
GPS
Indefinite-Lived Intangible Assets
Goodwill	18,500			$ 18,500
TRC
Indefinite-Lived Intangible Assets
Goodwill						12,300
APC
Indefinite-Lived Intangible Assets
Impairment loss		$ 2,100
Trade names
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life				15 years
Finite Lived Intangible Assets - Gross Carrying Amount	8,323			$ 8,323
Accumulated Amortization	4,261			4,261
Finite Lived Intangible Assets - Net Amount	4,062			$ 4,062		4,424
Process certifications
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life				7 years
Finite Lived Intangible Assets - Gross Carrying Amount	1,897			$ 1,897
Accumulated Amortization	994			994
Finite Lived Intangible Assets - Net Amount	903			903		1,039
Customer relationships
Finite-Lived Intangible Assets
Finite Lived Intangible Assets - Gross Carrying Amount	1,346			1,346
Accumulated Amortization	766			766
Finite Lived Intangible Assets - Net Amount	$ 580			$ 580		$ 674
Customer relationships | Maximum
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life				10 years
Customer relationships | Minimum
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life				4 years