Stock-Based Compensation Plan (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing stock price (in dollars per share)	$ 23.57
Fair value of stock options	$ 1.3	$ 1.3	$ 2.6
Fair value of stock options granted per share (in dollars per share)	$ 14.10	$ 8.36	$ 12.04
Volatility factor (in hundredths)		50.00%
Remaining volatility factor (in hundredths)		50.00%
Average volatility of common shares	100.00%
Remaining unamortized stock-based compensation cost	2.1
Stock-based compensation cost recognition period	2 years 1 month 6 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	1.4	1.3	1.1
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense recorded	0.1	0	0
Remaining unamortized stock-based compensation cost	0.6
Stock-based compensation cost recognition period	3 years 4 months 24 days
Vesting period of stock options (in years)	4 years
Restricted stock granted (in shares)	28,150
Restricted common stock value	$ 0.7
Number of granted restricted stock, vested	0

Average Volatility Of Common Shares

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

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The fair value of stock options issued during the period valued on a per share basis.

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No definition available.

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- Definition

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

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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.

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No definition available.

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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.

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The total fair value of shares issued during the period under a deferred compensation arrangement.

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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.

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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.

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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).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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