CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2013	Sep. 30, 2012
Preferred stock, par value (USD per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	79,807,305	79,790,557
Common stock, shares outstanding	66,345,436	66,328,688
Treasury stock, shares	13,461,869	13,461,869