Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2011	Sep. 30, 2011
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 3,290	$ 3,902
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000	5,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000	500,000
Common stock, shares issued	118,620	116,937
Common stock, shares outstanding	118,620	116,937