Long-term Debt (Details 4) (USD $)	9 Months Ended		3 Months Ended			3 Months Ended					3 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2012 8.75% Convertible senior subordinated notes due February 2016	Jun. 30, 2013 8.75% Convertible senior subordinated notes due February 2016	Sep. 30, 2012 8.75% Convertible senior subordinated notes due February 2016	Jun. 30, 2013 2.50% Convertible senior subordinated notes due February 2014	Mar. 31, 2013 2.50% Convertible senior subordinated notes due February 2014	Jun. 30, 2012 2.50% Convertible senior subordinated notes due February 2014	Dec. 31, 2011 2.50% Convertible senior subordinated notes due February 2014	Sep. 30, 2012 2.50% Convertible senior subordinated notes due February 2014	Jun. 30, 2012 14.75% Convertible senior subordinated notes due 2014	Mar. 31, 2012 14.75% Convertible senior subordinated notes due 2014	Jun. 30, 2012 16% Convertible senior subordinated notes due 2016
Long-term debt
Additional borrowings			$ 49,800,000
Interest rate on secured notes (as a percent)			8.75%	8.75%	8.75%	2.50%	2.50%	2.50%	2.50%	2.50%	14.75%	14.75%	16.00%
Repurchase and cancellation of convertible senior subordinated notes			49,800,000			24,300,000	15,300,000	5,000,000	7,500,000		1,000,000		9,200,000
Cash consideration paid for cancelation of convertible senior subordinated notes			600,000			24,500,000	15,200,000	4,700,000	5,500,000
Gain on extinguishment of debt	35,000	2,350,000						300,000	2,000,000
Write-off of unamortized balances of debt discount and debt issue costs			4,500,000			1,300,000	800,000	500,000	900,000		200,000	700,000
Debt instrument early repayment premium											$ 100,000	$ 1,600,000