COMMITMENTS - Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Operating leases, options to extend	true
Operating leases, options to terminate	true
Operating lease expense	$ 3,391	$ 1,820	$ 1,004
Operating lease payments	$ 3,300	2,000
Weighted average lease term	46 months
Weighted average discount rate	2.50%
Future minimum lease payment	$ 3,500	3,000
Unsatisfied bonded performance obligations	235,100
April 30, 2022	1,457
Bonds outstanding, covering other risks	1,000
Company's expense for defined contribution savings plans	$ 2,300	1,900	1,700
Minimum
Deferred period	5 years
Maximum
Deferred period	7 years
London Interbank Offered Rate (LIBOR)
Interest rate margin on referred rate	1.60%
TRC
April 30, 2022	$ 300
GPS | Financial guarantee
Guarantor obligation maximum exposure	3,600
SMC
April 30, 2022	100
Costs of Revenues [Member]
Rent expense	12,000	7,100	4,000
Selling, General and Administrative Expenses [Member]
Rent expense	$ 1,000	$ 900	$ 700