Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Revenues	$ 135,588	$ 122,130	$ 368,676	$ 313,819
Cost of goods sold	111,873	103,755	310,255	272,469
Gross profit	23,715	18,375	58,421	41,350
Selling, general and administrative expenses	17,117	16,174	50,240	48,462
Research and development expenses	1,631	1,632	4,988	4,926
Amortization of intangible assets	44	44	132	161
Insurance proceeds	(950)	0	(950)	0
Restructuring and other, net	233	0	233	0
Operating income (loss)	5,640	525	3,778	(12,199)
Other income	0	0	0	(507)
Interest expense	59	51	170	153
Interest income	(305)	(215)	(707)	(711)
Income (loss) before income taxes	5,886	689	4,315	(11,134)
Income tax expense (benefit)	797	388	963	(2,443)
Net income (loss)	$ 5,089	$ 301	$ 3,352	$ (8,691)
Income (loss) per share:
Basic (in dollars per share)	$ 0.44	$ 0.03	$ 0.29	$ (0.76)
Diluted (in dollars per share)	$ 0.44	$ 0.03	$ 0.29	$ (0.76)
Weighted average shares:
Basic (in shares)	11,579	11,514	11,567	11,503
Diluted (in shares)	11,603	11,587	11,589	11,503
Dividends per share (in dollars per share)	$ 0.26	$ 0.26	$ 0.78	$ 0.78