An amount calculated as a basis for determining the effects of amortization expenses and other deferrals.

No definition available.

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- Definition

The maximum discretionary contribution % by the company for eligible employees based on service.

+ References

No definition available.

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- Definition

The minimum discretionary contribution % by the company for eligible employees based on service.

+ References

No definition available.

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- Definition

The minimum non-elective contribution % by the company to all employees eligible for the defined contribution retirement plan. Contributions are concurrent with each payroll period and are non-forfeitable and vest immediately.

+ References

No definition available.

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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- Definition

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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- Definition

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.

+ References

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- Definition

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.

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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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PENSION AND POSTRETIREMENT PLANS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2012 Defined Benefit Plans [Member]	Mar. 31, 2012 Defined Benefit Plans [Member]	Sep. 30, 2012 Post-Retirement Medical Plan [Member]	Mar. 31, 2012 Post-Retirement Medical Plan [Member]
Defined Benefit Plan Disclosures [Line Items]
Minimum non-elective contribution (NEC) % for the 401(K) plan (in hundredths)	3.00%
Discretionary contribution % for the 401(K) plan, range mininum	1.00%
Discretionary contribution % for the 401(K) plan, range maximum	3.00%
Defined contribution retirement plan cost	$ 12.9	$ 12.5
Defined Benefit Plan and Postretirement Plan Disclosure
Service cost for benefits earned			0.6	0.6	0.1	0.1
Interest cost on benefit obligation			3.7	3.7	0.6	0.6
Expected return on plan assets			(4.3)	(4.4)
Net amortization and deferral			3.0	3.1	0.2	0
Defined benefit/postretirement plan costs			$ 3.0	$ 3.0	$ 0.9	$ 0.7