Employee Benefits (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Employee Benefits (Textuals) [Abstract]
Contribution towards retirement plans			$ 14.6
Expected contribution towards retirement plans	15		15
Retirement Plans [Member]
Components of net periodic cost for retirement plans and post-retirement plans
Service cost	15.9	14.4	33.5	30.6
Interest cost	24.7	23.2	49.6	46.9
Expected return on assets	(31.9)	(27.8)	(63.7)	(55.7)
Amortization of prior service credit	(0.1)		(0.2)	(0.1)
Amortization of actuarial loss	8.0	3.6	15.3	7.4
Net periodic benefit cost	16.6	13.4	34.5	29.1
Post-Retirement Plans [Member]
Components of net periodic cost for retirement plans and post-retirement plans
Service cost	0.7	0.6	1.4	1.2
Interest cost	1.7	1.7	3.4	3.7
Amortization of prior service credit	(0.3)	(0.3)	(0.6)	(0.6)
Amortization of actuarial loss		(0.1)	0.1
Net periodic benefit cost	$ 2.1	$ 1.9	$ 4.3	$ 4.3

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The amount of gains or losses recognized in net periodic benefit cost.

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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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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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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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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.

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