BUSINESS SEGMENT INFORMATION (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
BUSINESS SEGMENT INFORMATION
Net sales	$ 249,129	$ 229,136	$ 467,443	$ 434,637
EBIT	32,447	25,619	54,568	46,176
Less: Interest expense	(3,226)	(2,269)	(5,893)	(3,927)
Earnings before income taxes	29,221	23,350	48,675	42,249
A&D
BUSINESS SEGMENT INFORMATION
Net sales	114,701	98,982	209,434	181,965
EBIT	23,377	18,795	40,040	31,331
USG
BUSINESS SEGMENT INFORMATION
Net sales	87,309	79,161	170,293	150,206
EBIT	17,575	14,061	35,200	30,192
Test
BUSINESS SEGMENT INFORMATION
Net sales	47,119	50,993	87,716	102,466
EBIT	5,542	7,226	7,321	12,637
Corporate (loss)
BUSINESS SEGMENT INFORMATION
EBIT	$ (14,047)	$ (14,463)	$ (27,993)	$ (27,984)