LONG-TERM DEBT - Senior Subordinated Notes (Details) - USD ($)	Jun. 30, 2015	Sep. 30, 2014	Aug. 31, 2013	Mar. 31, 2012	Feb. 28, 2005
Debt Instrument [Line Items]
Accrued interest payable	$ 28,718,000	$ 8,659,000
2005 6 7/8% Senior Subordinated Notes | Senior Subordinated Notes
Debt Instrument [Line Items]
Loan face amount					$ 150,000,000.0
Note stated interest rate	6.875%	6.875%			6.875%
Principal amount tendered and exchanged				$ 140,300,000
Debt outstanding	$ 9,700,000
Accrued interest payable		$ 83,000
2012 11 % Senior Subordinated Notes | Senior Subordinated Notes
Debt Instrument [Line Items]
Loan face amount				$ 344,200,000.0
Note stated interest rate	11.00%	11.00%		11.00%
Redeemable rate before cutoff				100.00%
Redeemable rate after cutoff				101.00%
Redeemable rate upon certain conditions				100.00%
Payment in Kind (PIK) interest rate				2.00%
Debt instrument, repurchase amount			$ 69,000,000
Notes payable	$ 275,200,000
Accrued interest payable	$ 8,900,000	$ 1,300,000
2012 11 % Senior Subordinated Notes | Senior Subordinated Notes | 2004 Senior Subordinated Notes
Debt Instrument [Line Items]
Principal amount tendered and exchanged				$ 203,800,000
2012 11 % Senior Subordinated Notes | Senior Subordinated Notes | 2005 Senior Subordinated Notes
Debt Instrument [Line Items]
Principal amount tendered and exchanged				$ 140,300,000