PURCHASED INTANGIBLE ASSETS - Goodwill and Finite Lived Intangible Assets (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 01, 2019	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2016
Finite-Lived Intangible Assets
Intangible Assets - Gross Carrying Amount		$ 11,566
Accumulated Amortization		6,565
Finite Lived Intangible Assets - Net Amount		5,001
Other intangible assets, net		5,001	$ 6,137
Additions to other intangible assets		0	0	$ 0
Additions to impairment losses		0	0
Amortization of purchased intangible assets		1,136	1,012	1,032
Indefinite-Lived Intangible Assets
Goodwill allocated for income tax reporting purposes		$ 16,400
Period of amortization of goodwill for income tax purpose		15 years
Impairment loss		$ 4,895	1,491	584
APC
Finite-Lived Intangible Assets
Percentage of goodwill acquired					100.00%
TRC
Finite-Lived Intangible Assets
Percentage of average annual growth in revenues over the next seven years	4.70%
Expected annual growth in revenues period	7 years
Expected terminal value annual growth rate	3.00%
Percentage of average annual growth in earnings before interest and taxes by the year ending January 31, 2027	6.50%
Percentage of average annual growth in earnings before interest and taxes for the year ending January 31, 2021	4.80%
Percentage of goodwill acquired					34.00%
Indefinite-Lived Intangible Assets
Goodwill Impairment Loss	$ 2,800		1,500	600
TRC
Indefinite-Lived Intangible Assets
Impairment loss		2,823	1,491	$ 584
APC
Indefinite-Lived Intangible Assets
Impairment loss		$ 2,072
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		3,193
Finite Lived Intangible Assets - Net Amount		$ 450	694
Trade names | TRC
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		15 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 4,499
Accumulated Amortization		1,250
Finite Lived Intangible Assets - Net Amount		3,249	3,549
Trade names | SMC | Trade names | SMC
Finite-Lived Intangible Assets
Accumulated Amortization		181
Indefinite-lived Intangible Assets		$ 181	181
Process certifications
Finite-Lived Intangible Assets
Finite-Lived Intangible Assets - Estimated Useful Life		7 years
Finite Lived Intangible Assets - Gross Carrying Amount		$ 1,897
Accumulated Amortization		1,129
Finite Lived Intangible Assets - Net Amount		768	1,039
Customer relationships
Finite-Lived Intangible Assets
Finite Lived Intangible Assets - Gross Carrying Amount		1,346
Accumulated Amortization		812
Finite Lived Intangible Assets - Net Amount		$ 534	$ 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