Common Stock (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended		3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2012 2002 Stock Plan	Sep. 30, 2011 2002 Stock Plan	Mar. 31, 2012 2005 Stock Plan	Sep. 30, 2011 2005 Stock Plan
Share-Based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Authorized					60,440	67,032	925,119	932,438
Terms of Award					The term of any option may not exceed ten years from the date of grant.		The compensation committee will determine the number and type of stock-based awards to each participant, the exercise price of each award, the duration of the award (not to exceed ten years), vesting provisions and all other terms and conditions of such award in individual award agreements.
Number Of Outstanding Options							26,148
Weighted Average Exercise Price							$ 17.56
Share-based Compensation Arrangement by Share-based Payment Award, Additional Disclosures [Abstract]
Shares Issued During Period			5,750	3,000
Compensation Expense	$ 427	$ 657	$ 868	$ 904
Employee Stock Purchase Plan [Abstract]
Employee Stock Purchase Plan Discount Rate	95.00%
Employee Stock Purchase Plan Payroll Deduction Rate Minimum	1.00%
Employee Stock Purchase Plan Payroll Deduction Rate Maximum	10.00%
Employee Stock Purchase Plan Annual Limit	$ 20
Employee Stock Purchase Plan Share Limit Per Period	200
ESPP Shares Issued	3,520	3,070