SEGMENTS - Schedule of Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Mar. 31, 2025
Segment Reporting Information [Line Items]
Revenues, net	$ 276,951	$ 227,926	$ 540,597	$ 454,103
Cost of revenues	157,766	124,025	305,970	242,781
Selling, general, and administrative expenses	62,405	52,352	122,971	104,712
Operating income	56,780	51,549	111,656	106,610
Depreciation & amortization	14,391	9,950	27,729	19,883
Capital expenditures	3,080	5,486	5,984	8,587
Total assets	1,517,953		1,517,953		$ 1,379,065
Contractor Solutions
Segment Reporting Information [Line Items]
Revenues, net	206,278	156,764	401,253	315,302
Reportable Segments
Segment Reporting Information [Line Items]
Revenues, net	276,951	227,926	540,597	454,103
Cost of revenues	160,003	126,140	310,003	246,822
Selling, general, and administrative expenses	55,886	45,746	109,328	90,408
Operating income	63,299	58,155	125,299	120,914
Depreciation & amortization	14,342	9,905	27,635	19,796
Capital expenditures	3,080	5,403	5,984	8,488
Total assets	1,501,479		1,501,479		1,168,097
Reportable Segments \| Contractor Solutions
Segment Reporting Information [Line Items]
Revenues, net	206,278	156,764	401,253	315,302
Cost of revenues	114,424	82,494	220,890	163,802
Selling, general, and administrative expenses	40,669	30,086	78,185	59,312
Operating income	53,375	46,254	106,133	96,138
Depreciation & amortization	12,555	8,002	24,095	15,985
Capital expenditures	2,398	4,550	4,476	6,646
Total assets	1,272,563		1,272,563		941,087
Reportable Segments \| Specialized Reliability Solutions
Segment Reporting Information [Line Items]
Revenues, net	38,764	38,489	75,540	75,235
Cost of revenues	25,845	24,530	49,466	46,064
Selling, general, and administrative expenses	7,868	8,185	15,811	16,294
Operating income	5,093	5,819	10,336	12,970
Depreciation & amortization	1,347	1,409	2,684	2,832
Capital expenditures	409	647	1,131	1,161
Total assets	143,642		143,642		145,663
Reportable Segments \| Engineered Building Solutions
Segment Reporting Information [Line Items]
Revenues, net	31,909	32,673	63,804	63,566
Cost of revenues	19,734	19,116	39,647	36,956
Selling, general, and administrative expenses	7,349	7,475	15,332	14,802
Operating income	4,831	6,082	8,830	11,806
Depreciation & amortization	440	494	856	979
Capital expenditures	273	206	377	681
Total assets	85,274		85,274		81,347
Intersegment revenue
Segment Reporting Information [Line Items]
Revenues, net	2,237	2,115	4,033	4,041
Intersegment revenue \| Contractor Solutions
Segment Reporting Information [Line Items]
Revenues, net	2,190	2,070	3,955	3,950
Intersegment revenue \| Specialized Reliability Solutions
Segment Reporting Information [Line Items]
Revenues, net	42	45	73	91
Intersegment revenue \| Engineered Building Solutions
Segment Reporting Information [Line Items]
Revenues, net	5	0	5	0
Eliminations and Other
Segment Reporting Information [Line Items]
Revenues, net	(2,237)	(2,115)	(4,033)	(4,041)
Cost of revenues	(2,237)	(2,115)	(4,033)	(4,041)
Selling, general, and administrative expenses	6,519	6,606	13,643	14,304
Operating income	(6,519)	(6,606)	(13,643)	(14,304)
Depreciation & amortization	49	45	94	87
Capital expenditures	0	$ 83	0	$ 99
Total assets	$ 16,474		$ 16,474		$ 210,968

CSW INDUSTRIALS, INC. 10-Q