LONG-TERM DEBT - Senior Subordinated Notes (Details) (USD $)	Jun. 30, 2013	Sep. 30, 2012	Jun. 30, 2013 Senior Subordinated Notes 2004 7 1/8% Senior Subordinated Notes	Sep. 30, 2012 Senior Subordinated Notes 2004 7 1/8% Senior Subordinated Notes	Mar. 06, 2012 Senior Subordinated Notes 2004 7 1/8% Senior Subordinated Notes	Aug. 31, 2004 Senior Subordinated Notes 2004 7 1/8% Senior Subordinated Notes	Jun. 30, 2013 Senior Subordinated Notes 2005 6 7/8% Senior Subordinated Notes	Sep. 30, 2012 Senior Subordinated Notes 2005 6 7/8% Senior Subordinated Notes	Mar. 06, 2012 Senior Subordinated Notes 2005 6 7/8% Senior Subordinated Notes	Feb. 28, 2005 Senior Subordinated Notes 2005 6 7/8% Senior Subordinated Notes	Jun. 30, 2013 Senior Subordinated Notes 2012 11 % Senior Subordinated Notes	Sep. 30, 2012 Senior Subordinated Notes 2012 11 % Senior Subordinated Notes	Mar. 06, 2012 Senior Subordinated Notes 2012 11 % Senior Subordinated Notes	Mar. 06, 2012 Senior Subordinated Notes 2012 11 % Senior Subordinated Notes 2004 Senior Subordinated Notes	Mar. 06, 2012 Senior Subordinated Notes 2012 11 % Senior Subordinated Notes 2005 Senior Subordinated Notes
Debt Instrument [Line Items]
Loan face amount						$ 225,000,000.0				$ 150,000,000.0			$ 344,200,000
Note stated interest rate			7.125%			7.125%	6.875%			6.875%	11.00%		11.00%
Redeemable rate before cutoff													100.00%
Redeemable rate after cutoff													101.00%
Redeemable rate upon certain conditions													100.00%
Principal amount tendered and exchanged					203,800,000				140,300,000					203,800,000	140,300,000
Debt outstanding	1,680,415,000	1,697,415,000	21,156,000	21,156,000			9,654,000	9,654,000			344,190,000	344,190,000
Payment in Kind (PIK) interest rate													2.00%
Accrued interest	$ 24,395,000	$ 46,362,000	$ 565,000	$ 148,000			$ 249,000	$ 56,000			$ 11,100,000	$ 1,700,000