Equity-Based Compensation (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Curtailment loss		$ 0
Shares available for future grants	10.8
Equity-based compensation	27.2us-gaap_ShareBasedCompensation	27.1us-gaap_ShareBasedCompensation	25.6us-gaap_ShareBasedCompensation
Weighted average grant date fair value	$ 10.11	$ 15.16	$ 14.29
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised	0.6	4.3	9.6
Tax benefit from equity-based compensation expense		1.4	4.6
Adjustment to Additional Paid In Capital resulting from income tax effect of equity-based compensation	6.5
Unrecognized compensation costs	2.0
Weighted average period for recognition of equity-based compensation expense	1 year 10 months 13 days
Cash received in relation to stock options	1.5
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Adjustment to Additional Paid In Capital resulting from income tax effect of equity-based compensation	0.3
Unrecognized compensation costs	18.3
Weighted average period for recognition of equity-based compensation expense	2 years 1 month 7 days
Award vesting period	3 years
Total fair value of stock that vested during the period	26.8	19.8	16.7
Income tax expense (benefit) related to restricted stock compensation	0.5	0.1	0.3
Weighted average grant date fair value	$ 31.40	$ 30.06	$ 30.54
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs	2.3
Weighted average period for recognition of equity-based compensation expense	1 year 10 months 24 days
Weighted average grant date fair value	$ 31.57	$ 30.12	$ 30.75
Continuing Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation	21.4	25.7	25.6
Discontinued Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation	$ 5.8	$ 1.4

Employee Service Share-Based Compensation Tax Expense

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

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- Definition

The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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-Publisher FASB

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Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Name Accounting Standards Codification

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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