Borrowings - Schedule of Long-term Debt (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013	Feb. 01, 2013
Debt Instrument [Line Items]
Unamortized debt discounts	$ (4,780)	$ (5,160)
Long-term debt	1,511,873	1,512,183
Senior Notes [Member]
Debt Instrument [Line Items]
Unamortized debt discounts	(4,780)	(5,160)
Long-term debt	1,411,007	1,416,860
Senior Notes [Member] | 8 1/8% Senior Notes Maturing June 2016
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.125%	8.125%
Senior notes	172,879	172,879
Senior Notes [Member] | 6 5/8% Senior Secured Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%	6.625%
Senior notes	300,000	300,000
Senior Notes [Member] | 9 1/8% Senior Notes Maturing June 2018
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.125%	9.125%
Senior notes	298,000	298,000
Senior Notes [Member] | 9 1/8% Senior Notes Maturing May 2019
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.125%	9.125%
Senior notes	235,000	235,000
Senior Notes [Member] | 7 1/2% Senior Notes Maturing September 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.50%	7.50%
Senior notes	200,000	200,000
Senior Notes [Member] | 7 1/4% Senior Notes Maturing February 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%	7.25%	7.25%
Senior notes	200,000	200,000
Senior Notes [Member] | TEU Senior Amortizing Notes
Debt Instrument [Line Items]
Senior notes	9,908	16,141
Junior Subordinated Notes
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.987%
Unamortized debt discounts	(46,100)
Long-term debt	54,703	53,670
Cash Secured Loan
Debt Instrument [Line Items]
Long-term debt	22,368	22,368
Other Secured Notes Payable
Debt Instrument [Line Items]
Long-term debt	$ 23,795	$ 19,285