Stockholders' Equity (Details) (USD $)	0 Months Ended	12 Months Ended				12 Months Ended			12 Months Ended				3 Months Ended		0 Months Ended	3 Months Ended			12 Months Ended
	Jul. 17, 2012	Sep. 30, 2014 offering	Sep. 30, 2013	Sep. 30, 2012	Mar. 31, 2012	Sep. 30, 2014 TEU Senior Amortizing Notes Maturing August 2015	Sep. 30, 2014 TEU Senior Amortizing Notes Maturing August 2015 Senior Notes	Sep. 30, 2013 TEU Senior Amortizing Notes Maturing August 2015 Senior Notes	Sep. 30, 2014 Tangible Equity Units Senior Notes	Jul. 17, 2012 Tangible Equity Units Senior Notes TEUs	Mar. 31, 2012 Tangible Equity Units Senior Notes TEUs	Sep. 30, 2014 7.5% Senior Amortizing Note Maturing July 15, 2015	Mar. 31, 2012 7 1/2% Mandatory Convertible Subordinated Notes Convertible Subordinated Debt	Sep. 30, 2014 7 1/2% Mandatory Convertible Subordinated Notes Convertible Subordinated Debt	Jul. 17, 2012 Common Stock	Sep. 30, 2014 Common Stock	Mar. 31, 2013 Common Stock	Mar. 31, 2012 Common Stock	Sep. 30, 2014 Common Stock	Sep. 30, 2013 Common Stock	Sep. 30, 2014 Range 1 TEU Senior Amortizing Notes Maturing August 2015	Sep. 30, 2014 Range 2 TEU Senior Amortizing Notes Maturing August 2015	Sep. 30, 2014 Range 3 TEU Senior Amortizing Notes Maturing August 2015
Class of Stock [Line Items]
Authorized number of shares		63,000,000	63,000,000	100,000,000
Equity Instrument Convertible Number of Equity Instruments									3,700,000
Shares of common stock exchanged for the 2010 TEUs																156,975				2,800,000
Tangible Equity Units (TEUs) issued during period (units)										4,600,000	2,800,000
Debt instrument stated interest rate (percent)										7.50%		7.50%
Percentage of original issuance of 2010 TEUs that were exchanged					94.00%
Amortizing notes outstanding							$ 6,703,000	$ 16,141,000
Number of common stock exchanged for debt (shares)																	408,790	2,200,000
Value of convertible debt exchanged for common stock													48,100,000
Long-term debt														9,400,000
Number of shares in underwritten public offering (shares)															4,400,000
Proceeds from issuance of TEU prepaid stock purchase contracts	171,400,000
Number of offerings		2
Number of shares surrendered by emloyees (shares)		23,602	6,147	9,156
Aggregate value of stock surrendered		$ 450,000	$ 121,000	$ 126,000
382 Ownership Limitation		4.95%
Stock Issued During Period, Shares, Conversion of Units																			1,368,108
Debt Instrument, Convertible, Conversion Ratio						1.5372															1.72414	1.40746	25.00
Tangible Equity Units TEUs Converted									890,000												115,433	1,252,675
Debt Instrument, Convertible, Stock Price Trigger																					$ 14.50	$ 17.75
Debt Instrument, Convertible, Number of Equity Instruments									5,200,000
Common Stock, Par or Stated Value Per Share		$ 0.001	$ 0.001