COMMITMENTS - Leases (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Operating leases, options to extend			true
Operating leases, options to terminate			true
Operating lease expense	$ 1,100	$ 400	$ 1,938	$ 793
Operating lease payments	$ 1,100	400	$ 1,900	800
Weighted average lease term	27 months		27 months
Weighted average discount rate	2.90%		2.90%
Future minimum lease payment			$ 800	1,500
Unsatisfied bonded performance obligations	$ 295,900		295,900
April 30, 2022	743		743
Bonds outstanding, covering other risks			$ 5,700
London Interbank Offered Rate (LIBOR)
Interest rate margin on referred rate			1.60%
TRC
April 30, 2022	300		$ 300
GPS | Financial guarantee
Guarantor obligation maximum exposure	3,600		3,600
Costs of Revenues
Rent expense	3,300	1,400	6,300	2,000
Selling, General and Administrative Expenses
Rent expense	$ 300	$ 200	$ 500	$ 400