Stockholders' Equity - Additional Information (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Stockholders' Equity (Textual) [Abstract]
Percent of outstanding common stock granted to employees	10.00%
Options have a term	5 years 10 months 24 days
Exercise price of stock option granted to employees	110.00%
Increments in option	25.00%
Stockholders' Equity (Additional Textual) [Abstract]
Stock options vested	106,500	102,500	104,500
Fair values of stock options vested	$ 0.8	$ 0.7	$ 0.3
Intrinsic value of exercised options	10.4	4.0	20.8
Unvested compensation expense	0.2
Period for recognition of Unvested Compensation Expenses	1 year
Common stock split conversion ratio	2
Restricted Stock
Stockholders' Equity (Textual) [Abstract]
Restriction period for continuing to hold restricted stock	10 years
Outstanding shares of restricted stock	0
Maximum
Stockholders' Equity (Textual) [Abstract]
Outstanding shares of common stock granted to employees expiry term	5 years
Key Employee Stock Option Plan
Stockholders' Equity (Textual) [Abstract]
Common stock, shares issued	2,250,000
Common stock available	184,350
Payroll related expenditures	$ 0.9
Vesting Period for Option from date of grant	4 years
Key Employee Stock Option Plan | Maximum
Stockholders' Equity (Textual) [Abstract]
Options have a term	10 years