Employee Benefit Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Deferred Compensation Arrangement With Individual Post Retirement Benefits [Line Items]
Maximum annual contribution per employee percenatge	25.00%
Matching contributions, amount	$ 1.3	$ 1.3	$ 1.1
Full Employer Match [Member]
Deferred Compensation Arrangement With Individual Post Retirement Benefits [Line Items]
Employeer contribution percentage	100.00%
Employee contribution percentage	3.00%
Half Employer Match [Member]
Deferred Compensation Arrangement With Individual Post Retirement Benefits [Line Items]
Employeer contribution percentage	50.00%
Employee contribution percentage	2.00%