SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021 USD ($)	Jul. 31, 2020 USD ($)	Jul. 31, 2021 USD ($) segment	Jul. 31, 2020 USD ($)	Jan. 31, 2021 USD ($)
Segment Reporting Information
Operating segment | segment			1
Revenues	$ 133,008	$ 87,492	$ 259,349	$ 147,640
Cost of revenues	105,356	71,862	207,983	128,001
Gross profit	27,652	15,630	51,366	19,639
Selling, general and administrative expenses	10,331	9,085	20,223	19,429
Income (loss) from operations	17,321	6,545	31,143	210
Other (loss) income, net	(260)	451	452	1,539
Income (loss) before income taxes	17,061	6,996	31,595	1,749
Income tax (expense) benefit	(4,191)	(1,397)	(7,959)	3,057
Net income	12,870	5,599	23,636	4,806
Amortization of intangibles	225	226	453	451
Depreciation	859	921	1,741	1,858
Property, plant and equipment additions	167	449	1,011	1,133
Current assets	597,656	503,456	597,656	503,456	$ 546,220
Current liabilities	307,347	233,435	307,347	233,435	276,087
Goodwill	27,943	27,943	27,943	27,943	27,943
Total assets	651,989	561,107	651,989	561,107	$ 602,630
Other
Segment Reporting Information
Selling, general and administrative expenses	2,119	2,034	4,188	3,839
Income (loss) from operations	(2,119)	(2,034)	(4,188)	(3,839)
Other (loss) income, net	2	13	4	77
Income (loss) before income taxes	(2,117)	(2,021)	(4,184)	(3,762)
Depreciation	1	1	2	2
Property, plant and equipment additions	2		3
Current assets	174,823	121,905	174,823	121,905
Current liabilities	683	699	683	699
Total assets	175,158	122,211	175,158	122,211
Intercompany Eliminations
Segment Reporting Information
Revenues	1,200	1,100	3,200	1,700
Power Services
Segment Reporting Information
Revenues	99,004	69,039	196,176	117,651
Cost of revenues	78,496	55,610	157,165	101,320
Gross profit	20,508	13,429	39,011	16,331
Selling, general and administrative expenses	5,751	4,868	11,206	10,796
Income (loss) from operations	14,757	8,561	27,805	5,535
Other (loss) income, net	(262)	438	448	1,462
Income (loss) before income taxes	14,495	8,999	28,253	6,997
Amortization of intangibles	61	60	122	120
Depreciation	153	174	319	344
Property, plant and equipment additions	35	313	637	693
Current assets	389,998	356,383	389,998	356,383
Current liabilities	293,002	219,315	293,002	219,315
Goodwill	18,476	18,476	18,476	18,476
Total assets	422,902	389,380	422,902	389,380
Industrial Services
Segment Reporting Information
Revenues	30,153	16,689	56,811	26,433
Cost of revenues	23,847	14,896	45,816	23,878
Gross profit	6,306	1,793	10,995	2,555
Selling, general and administrative expenses	1,977	1,713	3,859	3,836
Income (loss) from operations	4,329	80	7,136	(1,281)
Income (loss) before income taxes	4,329	80	7,136	(1,281)
Amortization of intangibles	164	166	331	331
Depreciation	593	646	1,200	1,313
Property, plant and equipment additions	7	94	16	304
Current assets	29,084	23,244	29,084	23,244
Current liabilities	12,099	12,568	12,099	12,568
Goodwill	9,467	9,467	9,467	9,467
Total assets	48,655	46,099	48,655	46,099
Telecom Services
Segment Reporting Information
Revenues	3,851	1,764	6,362	3,556
Cost of revenues	3,013	1,356	5,002	2,803
Gross profit	838	408	1,360	753
Selling, general and administrative expenses	484	470	970	958
Income (loss) from operations	354	(62)	390	(205)
Income (loss) before income taxes	354	(62)	390	(205)
Depreciation	112	100	220	199
Property, plant and equipment additions	123	42	355	136
Current assets	3,751	1,924	3,751	1,924
Current liabilities	1,563	853	1,563	853
Total assets	$ 5,274	$ 3,417	$ 5,274	$ 3,417