Equity Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Maximum shares of common stock	20,000,000
Maximum annual shares awarded to employee	500,000
Shares available for granting additional awards	7,160,434
Unrecognized compensation cost of non-vested equity compensation awards	$ 14.5
Unrecognized compensation cost of non-vested equity compensation awards expected to be recognized over a weighted average period (years)	2 years 7 months 6 days
Number of options granted	0	0
Intrinsic value of stock options exercised	0.6	1.4
Stock Options \| Minimum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	24 months
Stock Options \| Maximum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	72 months
Restricted Stock \| Minimum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	12 months
Restricted Stock \| Maximum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	84 months
Performance Shares
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Fair value of awards vested	1.1
Number of performance awards granted	202,000	183,000
Number of performance awards earned	183,000
Performance Shares \| Minimum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	12 months
Performance awards, percentage range of target to be earned	0.00%	0.00%
Performance Shares \| Maximum
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Vesting period (months)	60 months
Performance awards, percentage range of target to be earned	132.00%	133.00%
Restricted Stock
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Number of restricted shares granted	0	0
Fair value of awards vested	$ 0	$ 0
Stock Options
Equity Compensation Arrangement by Share-based Payment Award [Abstract]
Maximum period for exercisable options (years and days)	10 years 1 day

Unrecognized cost of unvested share-based compensation awards.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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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.

+ References

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

-Publisher FASB

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Section 50

-Paragraph 2

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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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-Publisher FASB

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Net number of share options (or share units) granted during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

Performance Awards, percentage range of target to be earned.

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No definition available.

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The number of performance shares granted to participants.

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The number of performance awards that were earned during the reporting period based on the level of attainment of specified performance objectives.

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No definition available.

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The period of time, measured from grant date, before which an equity-based award expires as specified in the award agreement, 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 that can be awarded per participant per year under an employee share-based payment plan.

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No definition available.

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