Stock-Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified					12 Months Ended			3 Months Ended						0 Months Ended	3 Months Ended	12 Months Ended		12 Months Ended
	Sep. 30, 2012 Stock Options	Sep. 30, 2011 Stock Options	Sep. 30, 2010 Stock Options	Sep. 30, 2009 Stock Options	Sep. 30, 2012 Restricted Stock	Sep. 30, 2011 Restricted Stock	Sep. 30, 2010 Restricted Stock	Mar. 31, 2009 2007 Employee Stock Incentive Plan Stock-Based	Apr. 01, 2007 2007 Employee Stock Incentive Plan Stock-Based	Sep. 30, 2012 2007 Employee Stock Incentive Plan Stock Options	Jan. 31, 2008 1998 Employee Stock Option Plan Stock-Based	Jan. 01, 1998 1998 Employee Stock Option Plan Stock-Based	Sep. 30, 2012 1998 Employee Stock Option Plan Stock Options	Jul. 31, 2005 Non-Employee Directors Stock Option Plan Stock-Based	Mar. 31, 2009 Non-Employee Directors Stock Option Plan Stock-Based	Sep. 30, 1996 Non-Employee Directors Stock Option Plan Stock-Based	Sep. 30, 2012 Non-Employee Directors Stock Option Plan Stock Options	Sep. 30, 2012 Maximum	Sep. 30, 2012 Maximum Stock-Based	Sep. 30, 2012 Minimum	Sep. 30, 2012 Minimum Stock-Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized										1,400,000			500,000				350,000
Shares Available	443,478								500,000	352,878	500,000	50,000	0				90,600
Options Outstanding	891,293	611,384	636,283	691,403						688,668			79,772				122,853
Stock Issued During Period, Shares, Share-based Compensation, Gross								900,000						200,000	150,000	100,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period																			10 years
Option vesting period (in years)																		4 years	4 years	1 year	1 year
Unamortized Expense Share Issuance					$ 0.8	$ 0.8
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning Outstanding (in shares)					120,970	128,751	122,875
Awarded (in shares)					60,600	35,517	40,751
Released (in shares)					(51,595)	(43,298)	(33,625)
Forfeited (in shares)					(2,000)	0	(1,250)
Ending Outstanding (in shares)					127,975	120,970	128,751
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Beginning Outstanding, Weighted Average Grant Date Fair Value (usd per share)					$ 9.42	$ 6.34	$ 5.85
Awarded, Weighted Average Grant Date Fair Value (usd per share)					$ 7.98	$ 17.28	$ 8.00
Released, Weighted Average Grant Date Fair Value (usd per share)					$ 8.72	$ 6.78	$ 6.46
Forfeited, Weighted Average Grant Date Fair Value (usd per share)					$ 7.22	$ 0	$ 8.20
Ending Outstanding, Weighted Average Grant Date Fair Value (usd per share)					$ 9.06	$ 9.42	$ 6.34