Borrowings - Schedule of Long-term Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013 Senior Notes	Sep. 30, 2013 Senior Notes	Jul. 17, 2012 Senior Notes Tangible Equity Units	Dec. 31, 2013 Senior Notes 6 7/8% Senior Notes Maturing July 2015	Dec. 31, 2013 Senior Notes 8 1/8% Senior Notes Maturing June 2016	Sep. 30, 2013 Senior Notes 8 1/8% Senior Notes Maturing June 2016	Dec. 31, 2013 Senior Notes 6 5/8% Senior Secured Notes	Sep. 30, 2013 Senior Notes 6 5/8% Senior Secured Notes	Dec. 31, 2013 Senior Notes 9 1/8% Senior Notes Maturing June 2018	Sep. 30, 2013 Senior Notes 9 1/8% Senior Notes Maturing June 2018	Dec. 31, 2013 Senior Notes 9 1/8% Senior Notes Maturing May 2019	Sep. 30, 2013 Senior Notes 9 1/8% Senior Notes Maturing May 2019	Dec. 31, 2013 Senior Notes 7 1/2% Senior Notes Maturing September 2021 [Member]	Sep. 30, 2013 Senior Notes 7 1/2% Senior Notes Maturing September 2021 [Member]	Dec. 31, 2013 Senior Notes TEU Senior Amortizing Notes	Sep. 30, 2013 Senior Notes TEU Senior Amortizing Notes	Dec. 31, 2013 Senior Notes 7 1/4% Senior Notes Maturing February 2023 [Member]	Sep. 30, 2013 Senior Notes 7 1/4% Senior Notes Maturing February 2023 [Member]	Feb. 01, 2013 Senior Notes 7 1/4% Senior Notes Maturing February 2023 [Member]	Dec. 31, 2013 Junior Subordinated Notes	Sep. 30, 2013 Junior Subordinated Notes	Dec. 31, 2013 Cash Secured Loan	Sep. 30, 2013 Cash Secured Loan	Dec. 31, 2013 Other Secured Notes Payable	Sep. 30, 2013 Other Secured Notes Payable
Debt Instrument [Line Items]
Debt instrument stated interest rate (percent)					7.50%	6.875%	8.125%	8.125%	6.625%	6.625%	9.125%	9.125%	9.125%	9.125%	7.50%	7.50%			7.25%	7.25%	7.25%	7.987%
Senior notes							$ 172,879	$ 172,879	$ 300,000	$ 300,000	$ 298,000	$ 298,000	$ 235,000	$ 235,000	$ 200,000	$ 200,000	$ 14,227	$ 16,141	$ 200,000	$ 200,000
Unamortized debt discounts	(4,970)	(5,160)	(4,970)	(5,160)																		(46,600)
Long-term debt	$ 1,516,255	$ 1,512,183	$ 1,415,136	$ 1,416,860																		$ 54,187	$ 53,670	$ 22,368	$ 22,368	$ 24,564	$ 19,285