Fair Value Measurements (Details) (Assets and Liabilities Measured at Fair Value on a Recurring Basis [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	$ 57,798	$ 51,559
Cash equivalents [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	14,601	8,419
U.S. government and government agency obligations [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	32,774	30,603
Mortgage-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	3,305	3,948
Municipal Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	3,212	3,614
Asset-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	910	1,288
Corporate Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	2,119	2,497
Other [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	877	1,190
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	877	1,190
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Cash equivalents [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | U.S. government and government agency obligations [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Mortgage-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Municipal Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Asset-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Corporate Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] | Other [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	877	1,190
Significant Other Observable Inputs (Level 2) [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	56,921	50,345
Significant Other Observable Inputs (Level 2) [Member] | Cash equivalents [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	14,601	8,419
Significant Other Observable Inputs (Level 2) [Member] | U.S. government and government agency obligations [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	32,774	30,603
Significant Other Observable Inputs (Level 2) [Member] | Mortgage-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	3,305	3,933
Significant Other Observable Inputs (Level 2) [Member] | Municipal Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	3,212	3,614
Significant Other Observable Inputs (Level 2) [Member] | Asset-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	910	1,279
Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	2,119	2,497
Significant Other Observable Inputs (Level 2) [Member] | Other [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value	0
Significant Unobservable Inputs (Level 3) [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value		24
Significant Unobservable Inputs (Level 3) [Member] | Cash equivalents [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Significant Unobservable Inputs (Level 3) [Member] | U.S. government and government agency obligations [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Significant Unobservable Inputs (Level 3) [Member] | Mortgage-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value		15
Significant Unobservable Inputs (Level 3) [Member] | Municipal Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Significant Unobservable Inputs (Level 3) [Member] | Asset-backed securities [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value		9
Significant Unobservable Inputs (Level 3) [Member] | Corporate Bonds [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value
Significant Unobservable Inputs (Level 3) [Member] | Other [Member]
Schedule of assets and liabilities measured at fair value on a recurring basis
Total assets measured at fair value