CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Income Statement [Abstract]
Revenues	$ 448,716	$ 395,911	$ 565,243
Cost of goods sold	383,361	345,142	459,038
Gross profit	65,355	50,769	106,205
Selling, general and administrative expenses	66,768	61,524	74,924
Research and development expenses	6,717	6,906	6,731
Amortization of intangible assets	205	355	352
Restructuring and separation expenses	787	1,322	8,441
Operating income (loss)	(9,122)	(19,338)	15,757
Other income (See Note E)	(747)	(2,029)	(2,029)
Interest expense	207	168	149
Interest income	(883)	(558)	(156)
Income (loss) before income taxes	(7,699)	(16,919)	17,793
Income tax provision (benefit)	(547)	(7,433)	2,283
Net income (loss)	$ (7,152)	$ (9,486)	$ 15,510
Earnings (loss) per share:
Basic (in dollars per share)	$ (0.62)	$ (0.83)	$ 1.36
Diluted (in dollars per share)	$ (0.62)	$ (0.83)	$ 1.36
Weighted average shares:
Basic (in shares)	11,507	11,453	11,400
Diluted (in shares)	11,507	11,453	11,431
Dividends per share (in dollars per share)	$ 1.04	$ 1.04	$ 1.04