Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Dec. 31, 2012	Sep. 30, 2012
Condensed Consolidated Balance Sheets [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	30,250,370	30,222,132
Common stock, shares outstanding	24,363,343	24,891,205
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Treasury stock, at cost	5,887,027	5,330,927