Retirement Benefit Plans (Schedule of defined benefit plan obligations and assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair value of plan assets	$ 424.0	$ 413.0
Retirement Plans [Member]
Benefit obligation	(520.2)	(486.2)	(426.7)
Fair value of plan assets	420.6	407.1
Funded status	(99.6)	(79.1)
Amounts recognized in the Consolidated Balance Sheets:
Other assets	3.1	2.1
Accrued compensation and benefits	(102.7)	(81.2)
Medical Plan [Member]
Benefit obligation	(10.2)	(43.6)	(53.2)
Fair value of plan assets	7.2	10.0
Funded status	(3.0)	(33.6)
Amounts recognized in the Consolidated Balance Sheets:
Other assets	0	0
Accrued compensation and benefits	$ (3.0)	$ (33.6)

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This represents the entire assets recognized in the balance sheet that are associated with the defined benefit plans.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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- Definition

This represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans.

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