EMPLOYEE BENEFIT PLANS (DETAILS) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Current Fiscal Year	$ 11.1		$ 11.1
Qualified defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	9.0	8.1	18.0	16.2
Interest cost	18.3	16.9	36.6	33.8
Expected return on asets	(22.1)	(17.7)	(44.2)	(35.4)
Amortization of prior service cost	(0.2)	(0.2)	(0.4)	(0.4)
Actuarial loss	6.1	5.5	12.2	11.0
Net pension expense	11.1	12.6	22.2	25.2
Defined Benefit Plan, Contributions by Employer	11.1	15.2	22.2	30.4
Defined Benefit Plan, Minimum Required Contribution By Employer			0
Nonqualified defined benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension expense	0.9	0.8	1.8	1.6
Post retirement medical benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension expense	$ 3.7	$ 3.1	$ 7.4	$ 6.2

Defined Benefit Plan Minimum Require Contribution By Employer.

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- Definition

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.

+ References

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- Definition

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.

+ References

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- Definition

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

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- Definition

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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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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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.

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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.

+ References

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