Long-Term Debt (Schedule Of Long-term Debt) (Details) (USD $)	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2011 7-5/8% Senior Secured Notes [Member]	Mar. 31, 2011 7-5/8% Senior Secured Notes [Member]	Sep. 30, 2010 7-5/8% Senior Secured Notes [Member]	Jun. 30, 2011 11-3/8% Senior Secured Notes [Member]	Sep. 30, 2010 11-3/8% Senior Secured Notes [Member]	Oct. 31, 2009 11-3/8% Senior Secured Notes [Member]	Jun. 30, 2011 16% Convertible Senior Subordinated Notes Due 2016 [Member]	Sep. 30, 2010 16% Convertible Senior Subordinated Notes Due 2016 [Member]	Jun. 30, 2011 2.50% Convertible Senior Subordinated Notes Due 2014 [Member]	Sep. 30, 2010 2.50% Convertible Senior Subordinated Notes Due 2014 [Member]	Jun. 30, 2011 14.75% Convertible Senior Subordinated Notes Due 2014 [Member]	Sep. 30, 2010 14.75% Convertible Senior Subordinated Notes Due 2014 [Member]
Senior notes			$ 400,000,000	$ 400,000,000	$ 0	$ 0	$ 325,800,000	$ 328,300,000
Convertible senior subordinated notes	135,422,000	144,075,000							8,933,000	18,152,000	105,268,000	101,120,000	21,221,000	24,803,000
Carrying amount of long-term debt, net of discounts	535,422,000	469,875,000
Debt instrument, face amount	$ 553,000,000	$ 495,800,000				$ 328,250,000			$ 9,233,000	$ 19,277,000	$ 120,900,000		$ 22,905,000	$ 27,370,000