Employee Benefits (Net Periodic Cost) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net periodic benefit cost:
Service cost	$ 4.3us-gaap_DefinedBenefitPlanServiceCost	$ 4.3us-gaap_DefinedBenefitPlanServiceCost	$ 3.9us-gaap_DefinedBenefitPlanServiceCost
Interest cost	60.7us-gaap_DefinedBenefitPlanInterestCost	56.2us-gaap_DefinedBenefitPlanInterestCost	59.3us-gaap_DefinedBenefitPlanInterestCost
Expected return on plan assets	(53.7)	(55.6)	(51.1)
Amortization of prior net loss	12.8	14.8	9.0
Net periodic pension cost	24.1	19.7	21.1
Other changes in plan assets and benefit obligations recognized in other comprehensive loss (income):
Net actuarial loss (gain) and other adjustments	126.3	(107.7)	170.4
Less amortization of prior losses	(12.8)	(14.8)	(9.0)
Total recognized in other comprehensive loss (income)	113.5	(122.5)	161.4
Total recognized in net periodic benefit cost and other comprehensive (income) loss	137.6	(102.8)	182.5
Income tax provision (benefit) related to amounts in other comprehensive income	$ (3.2)	$ 42.7	$ (1.3)

Amount recognized in net periodic benefit cost and other comprehensive income.

No definition available.

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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

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Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

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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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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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