PURCHASED INTANGIBLE ASSETS - Goodwill and Finite Lived Intangible Assets (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2016	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Finite-Lived Intangible Assets
Goodwill		$ 34,913	$ 37,405	$ 18,476
Goodwill allocated for income tax reporting purposes		14,400
Percentage of contract backlog suspended	90.00%
Impairment loss		$ 1,979
Period of amortization of goodwill for income tax purpose		15 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 11,854
Accumulated Amortization		3,673	2,510	1,979
Finite Lived Intangible Assets - Net Amount		8,000
Intangible assets, net		8,181	9,344
APC
Finite-Lived Intangible Assets
Impairment loss		2,000	0	$ 0
GPS
Finite-Lived Intangible Assets
Goodwill		18,500
TRC
Finite-Lived Intangible Assets
Goodwill		14,400
APC
Finite-Lived Intangible Assets
Goodwill		$ 2,000
Trade names | GPS
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		15 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 3,643
Accumulated Amortization		2,464
Finite Lived Intangible Assets - Net Amount		1,179	1,421
Trade names | TRC
Finite-Lived Intangible Assets
Finite Lived Intangible Assets - Gross Carrying Amount		4,499
Accumulated Amortization		350
Finite Lived Intangible Assets - Net Amount		$ 4,149	4,499
Process certifications | TRC
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		7 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 1,897
Accumulated Amortization		316
Finite Lived Intangible Assets - Net Amount		$ 1,581	1,852
Customer relationships | TRC
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		10 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 916
Accumulated Amortization		107
Finite Lived Intangible Assets - Net Amount		$ 809	901
Customer relationships | APC
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		4 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 430
Accumulated Amortization		167
Finite Lived Intangible Assets - Net Amount		263	371
Other intangibles
Finite-Lived Intangible Assets
Finite Lived Intangible Assets - Gross Carrying Amount		288
Accumulated Amortization		269
Finite Lived Intangible Assets - Net Amount		$ 19	$ 119