FAIR VALUE OF FINANCIAL INSTRUMENTS (Narrative) (Details) - USD ($)	Sep. 30, 2015	Sep. 30, 2014
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, carrying value	$ 1,685,946,000	$ 1,742,122,000
Credit valuation adjustment to total fair value percentage (less than 1%)	1.00%
6.5% Senior Notes [Member] | Senior Notes [Member]
Fair Value Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, carrying value	$ 655,946,000	$ 657,122,000
Principal amount	650,000,000
Long-term debt, fair value	$ 526,000,000