Product Warranty Obligation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Product Warranties Disclosures [Abstract]
Warranty period, minimum	1 year
Warranty period, maximum	5 years
Standard Product Warranty Accrual [Roll Forward]
Beginning balance	$ 1,021	$ 941	$ 877
Warranties issued	669	730	885
Settlements made	(627)	(650)	(821)
Ending balance	$ 1,063	$ 1,021	$ 941