Selected Balance Sheet Data (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Accounts receivable, net:
Accounts receivable	$ 27,142	$ 24,929
Less allowance for doubtful accounts	313	295
Total accounts receivable, net	26,829	24,634
Inventories:
Raw materials	21,171	18,159
Work in process	224	428
Finished goods	4,745	5,848
Total Inventories	26,140	24,435
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	45,951	44,744
Less accumulated depreciation and amortization	32,041	29,587
Total property, equipment and improvements, net	13,910	15,157	15,370
Land
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	1,800	1,800
Buildings
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	10,522	10,522
Improvements
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	3,863	3,763
Equipment
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	14,989	14,093
Purchased Software
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	12,296	11,971
Furniture and Fixtures
Property, Plant and Equipment, Net
Total property, equipment and improvements, gross	$ 2,481	$ 2,595