Borrowings - Schedule of Long-term Debt (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Senior Notes	Sep. 30, 2011 Senior Notes	Sep. 30, 2012 Senior Notes 6 7/8% Senior Notes Maturing July 2015	Sep. 30, 2011 Senior Notes 6 7/8% Senior Notes Maturing July 2015	Sep. 30, 2012 Senior Notes 8 1/8% Senior Notes Maturing June 2016	Sep. 30, 2011 Senior Notes 8 1/8% Senior Notes Maturing June 2016	Sep. 30, 2012 Senior Notes 12% Senior Secured Notes Maturing October 2017	Jul. 31, 2012 Senior Notes 12% Senior Secured Notes Maturing October 2017	Sep. 30, 2011 Senior Notes 12% Senior Secured Notes Maturing October 2017	Sep. 30, 2012 Senior Notes 6 5/8% Senior Secured Notes Maturing April 2018	Jul. 31, 2012 Senior Notes 6 5/8% Senior Secured Notes Maturing April 2018	Sep. 30, 2011 Senior Notes 6 5/8% Senior Secured Notes Maturing April 2018	Sep. 30, 2012 Senior Notes 9 1/8% Senior Notes Maturing June 2018	Sep. 30, 2011 Senior Notes 9 1/8% Senior Notes Maturing June 2018	Sep. 30, 2012 Senior Notes 9 1/8% Senior Notes Maturing May 2019	Sep. 30, 2011 Senior Notes 9 1/8% Senior Notes Maturing May 2019	Sep. 30, 2012 Senior Notes TEU Senior Amortizing Notes Maturing August 2013	Sep. 30, 2011 Senior Notes TEU Senior Amortizing Notes Maturing August 2013	Sep. 30, 2012 Senior Notes TEU Senior Amortizing Notes Maturing August 2015	Sep. 30, 2011 Senior Notes TEU Senior Amortizing Notes Maturing August 2015	Sep. 30, 2012 Mandatory Convertible Subordinated Debt	Sep. 30, 2011 Mandatory Convertible Subordinated Debt	Sep. 30, 2012 Junior Subordinated Notes	Sep. 30, 2011 Junior Subordinated Notes	Jun. 15, 2006 Junior Subordinated Notes	Sep. 30, 2012 Cash Secured Loan	Sep. 30, 2011 Cash Secured Loan	Sep. 30, 2012 Other Secured Notes Payable	Sep. 30, 2011 Other Secured Notes Payable
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)					6.875%	6.875%	8.125%	8.125%	12.00%	12.00%	12.00%	6.625%	6.625%	6.625%	9.125%	9.125%	9.125%	9.125%							7.987%		7.987%
Senior notes					$ 172,454	$ 172,454	$ 172,879	$ 172,879	$ 0		$ 250,000	$ 300,000		$ 0	$ 300,000	$ 300,000	$ 235,000	$ 250,000	$ 316	$ 10,062	$ 23,500	$ 0
Unamortized debt discounts	(3,082)	(23,243)	(3,082)	(23,243)																					49,200
Total debt, net	$ 1,498,198	$ 1,488,826	$ 1,201,067	$ 1,132,152						$ 250,000													$ 9,402	$ 57,500	$ 51,603	$ 49,537		$ 227,368	$ 247,368	$ 8,758	$ 2,269