LONG-TERM DEBT - Senior Unsecured Notes (Details) - USD ($)	Jun. 30, 2015	Sep. 30, 2014	Aug. 31, 2013
Debt Instrument [Line Items]
Accrued interest payable	$ 28,718,000	$ 8,659,000
Senior Unsecured Notes \| 2013 9 3/4% Senior Unsecured Notes, due September 2021
Debt Instrument [Line Items]
Loan face amount			$ 500,000,000
Note stated interest rate	9.75%	9.75%	9.75%
Debt Instrument, Redeemable Rate			100.00%
Redeemable rate after cutoff			101.00%
Redeemable rate upon certain conditions			100.00%
Accrued interest payable	$ 16,300,000	$ 4,100,000

Debt Instrument, Redeemable Rate

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- Definition

Debt Instrument, Redeemable Rate Upon Certain Conditions

+ References

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- Definition

Debt Instrument, Redeemable Rate Upon Change of Control

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

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-Name Accounting Standards Codification

-Topic 210

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-Subparagraph (SX 210.5-02.20)

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