Share-Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized pre-tax compensation cost	$ 1.9
Weighted average recognition period (in years)	2 years 2 months 2 days
Total intrinsic value of options exercised during period	3.2	0.7
Cash received from options exercised during period	1.1	0.3
1992 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock authorized to be issued under plan (in shares)	14,900,000
Exercise price of shares granted may not be less than fair market value (percentage)	85.00%
2007 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock authorized to be issued under plan (in shares)	3,281,250
Exercise price of shares granted may not be less than fair market value (percentage)	100.00%
Unrecognized pre-tax compensation cost	$ 5.4
Weighted average recognition period (in years)	2 years 6 months
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period	2 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period	10 years
Restricted Stock [Member] \| 2007 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting period	20.00%
All Other Options Granted [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting period	20.00%
Director [Member] \| Options Granted Prior to May 25, 2004 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Exercisable period	9 years
Director [Member] \| Options Granted on or after May 25, 2004 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting period	33.33%

Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting, Percentage

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- Definition

The exercise price of granted shares may not be below this percentage of fair market value under the terms of the stock option plans.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable Period

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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- Definition

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.

+ References

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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

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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-Publisher FASB

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- Definition

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.

+ References

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-Publisher FASB

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