EMPLOYEE BENEFIT PLANS (Details) (USD $)	3 Months Ended	9 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer			$ 4,900,000
Service cost	1,194,000	992,000	3,582,000	2,976,000
Interest cost	2,094,000	2,049,000	6,283,000	6,147,000
Expected return on plan assets	(2,873,000)	(2,577,000)	(8,618,000)	(7,731,000)
Recognized actuarial loss	987,000	681,000	2,960,000	2,043,000
Prior service cost amortization	12,000	14,000	36,000	42,000
Recognized net initial obligation	0	0	0	0
Net periodic cost	1,414,000	1,159,000	4,243,000	3,477,000
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	836,000	704,000	2,508,000	2,112,000
Interest cost	1,211,000	1,204,000	3,634,000	3,612,000
Expected return on plan assets	(618,000)	(485,000)	(1,854,000)	(1,455,000)
Recognized actuarial loss	653,000	570,000	1,959,000	1,710,000
Prior service cost amortization	19,000	19,000	57,000	57,000
Recognized net initial obligation	89,000	89,000	267,000	267,000
Net periodic cost	2,190,000	2,101,000	6,571,000	6,303,000
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments in Year One	5,500,000		5,500,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Two	5,500,000		5,500,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Three	5,500,000		5,500,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Four	5,500,000		5,500,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Five	5,500,000		5,500,000
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payments in Year One	6,600,000		6,600,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Two	6,600,000		6,600,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Three	6,600,000		6,600,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Four	6,600,000		6,600,000
Defined Benefit Plan, Expected Future Benefit Payments in Year Five	$ 6,600,000		$ 6,600,000

The net increase or decrease of changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Gain or Loss
-URI http://asc.fasb.org/extlink&oid=6514294
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The amounts in accumulated other comprehensive income related to transition assets (obligations), origination from the adoption of FAS 87 and 106, expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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The increase in the fair value of plan assets from contributions made by the employer.

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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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The amount of the benefits expected to be paid in Year 5.

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The amount of the benefits expected to be paid in Year 4.

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The amount of the benefits expected to be paid in Year 1.

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The amount of the benefits expected to be paid in Year 3.

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The amount of the benefits expected to be paid in Year 2.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

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