Income Taxes (Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Statutory income tax amount	$ 5,233	$ 3,912	$ 1,890
State taxes, net of federal benefits	636	85	319
Transaction costs	0	2	60
Employee stock purchase plan	165	98	79
Foreign operations	984	1,552	556
Non-deductible executive compensation	373	291	150
Change in valuation allowance	0	0	(2,187)
Effective Income Tax Rate Reconciliation, Capital Loss Expiration	0	0	2,301
Utilization of research and development tax credits	(4,678)	(2,780)	(3,116)
Deferred balance sheet remeasure	0	0	(952)
ASU 2016-09 excess stock compensation	(1,678)	(2,967)	(1,131)
Contingent consideration	0	(1,239)	1,212
Changes from provision to return	181	413	(458)
Adjustment of tax contingency reserves	238	417	329
U.S. deduction for foreign export sales	(1,419)	(584)	(630)
Effective Income Tax Rate Reconciliation, GILTI, Amount	0	0	33
Other, net	113	45	178
Income tax (benefit) expense	$ 148	$ (755)	$ (1,367)