Closing stock price on the last trading day of the year ended.

No definition available.

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- Definition

Represents the percentage of stock options that vest during the first year of employment.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of stock options that vest each month following the first year of employment until fully vested.

+ References

No definition available.

+ Details

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- Details

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- Definition

Volatility factor derived from the average volatility of the Company's common shares since their initial public offering.

+ References

No definition available.

+ Details

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- Definition

Assumed volatility factor used in the calculation of fair values for stock options granted was derived from the average volatility of common shares for similar companies over a period.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

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-Paragraph 64

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 14.F)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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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- Definition

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

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- Definition

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

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

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-Number 123R

-Paragraph A240

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

+ 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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Stock-Based Compensation Plan (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Aggregate Intrinsic Value [Abstract]
Closing stock price (in dollars per share)	$ 23.27		$ 23.27
Volatility factor (in hundredths)			100.00%	50.00%
Remaining volatility factor (in hundredths)				50.00%
Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			1 year
Restricted Stock Grant [Abstract]
Vesting period of stock options (in years)			1 year
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			4 years
Percentage of stock options vesting after one year (in hundredths)			25.00%
Percentage of stock options vesting each month following first year (in hundredths)			2.083%
Restricted Stock Grant [Abstract]
Vesting period of stock options (in years)			4 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	$ 0.4	$ 0.3	$ 1.1	$ 0.9
Remaining unamortized stock-based compensation cost	2.2		2.2
Stock-based compensation cost recognition period			2 years 7 months 6 days
Aggregate Intrinsic Value [Abstract]
Aggregate intrinsic value of options exercised	2.3		2.3
Aggregate intrinsic value of options outstanding	11.2		11.2
Stock Options [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unamortized stock-based compensation cost	0.4		0.4
Stock-based compensation cost recognition period			8 months 12 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options (in years)			4 years
Stock-based compensation expense recorded	0.1		0.1
Remaining unamortized stock-based compensation cost	0.7		0.7
Stock-based compensation cost recognition period			3 years 8 months 12 days
Restricted Stock Grant [Abstract]
Restricted stock granted (in shares)			28,150
Restricted common stock value			$ 0.7
Vesting period of stock options (in years)			4 years