FAIR VALUE, HIERARCHY (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	$ 56,088		$ 50,349
Derivative Liabilities, Fair Value Disclosure	42,848		45,573
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	11,716	[1]	11,009	[1]
Other Assets, Fair Value Disclosure	1,129	[2]	30	[2]
Assets Fair Value Disclosure Total	68,933		61,388
Other Liabilities Fair Value Disclosure	0		0
Liabilities Fair Value Disclosure	42,848		45,573
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	11,716	[1]	11,009	[1]
Other Assets, Fair Value Disclosure	1,129	[2]	30	[2]
Assets Fair Value Disclosure Total	57,094		25,309
Other Liabilities Fair Value Disclosure	0		0
Liabilities Fair Value Disclosure	28,248		16,922
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]	0	[1]
Other Assets, Fair Value Disclosure	0	[2]	0	[2]
Assets Fair Value Disclosure Total	11,839		36,079
Other Liabilities Fair Value Disclosure	0		0
Liabilities Fair Value Disclosure	14,600		28,651
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]	0	[1]
Other Assets, Fair Value Disclosure	0	[2]	0	[2]
Assets Fair Value Disclosure Total	0		0
Other Liabilities Fair Value Disclosure	0		0
Liabilities Fair Value Disclosure	0		0
Physical Forward Commodity Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	11,823		20,248
Derivative Liabilities, Fair Value Disclosure	14,595		9,746
Physical Forward Commodity Contracts [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		0
Derivative Liabilities, Fair Value Disclosure	0		0
Physical Forward Commodity Contracts [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	11,823		20,248
Derivative Liabilities, Fair Value Disclosure	14,595		9,746
Physical Forward Commodity Contracts [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		0
Derivative Liabilities, Fair Value Disclosure	0		0
Financial Commodity Contracts - Natural Gas [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	44,249		29,915
Derivative Liabilities, Fair Value Disclosure	28,248		35,715
Financial Commodity Contracts - Natural Gas [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	44,249		14,270
Derivative Liabilities, Fair Value Disclosure	28,248		16,922
Financial Commodity Contracts - Natural Gas [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		15,645
Derivative Liabilities, Fair Value Disclosure	0		18,793
Financial Commodity Contracts - Natural Gas [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		0
Derivative Liabilities, Fair Value Disclosure	0		0
Financial Commodity Contracts - Foreign Exchange [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	16		186
Derivative Liabilities, Fair Value Disclosure	5		112
Financial Commodity Contracts - Foreign Exchange [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		0
Derivative Liabilities, Fair Value Disclosure	0		0
Financial Commodity Contracts - Foreign Exchange [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	16		186
Derivative Liabilities, Fair Value Disclosure	5		112
Financial Commodity Contracts - Foreign Exchange [Member] | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0		0
Derivative Liabilities, Fair Value Disclosure	$ 0		$ 0

[1] Included in other noncurrent assets on the Consolidated Balance Sheets.

[2] Includes various money market funds in Level 1.