Employer Share Plans (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Stock award activity
Outstanding at Dec 31, 2012, Number of Options	7,541
Outstanding at beginning of year, Weighted Average Exercise Price Per Share	$ 7.18
Granted, Number of Options
Granted, Weighted Average Exercise Price Per Share
Exercised or released, Number of Options
Exercised or released, Weighted Average Exercise Price Per Share
Expired or canceled, Number of Options	(53)
Expired or canceled, Weighted Average Exercise Price Per Share	$ 7.47
Outstanding at Mar 31, 2013 , Number of Options	7,488
Outstanding at March 31, 2013, Weighted Average Exercise Price Per Share	$ 7.18
Exercisable at March 31, 2013	3,933
Exercisable, Weighted Average Exercise Price at March 31, 2013	$ 7.64
Restricted stock awards [Member]
Stock award activity
Outstanding at December 31, 2012 , Number of Shares	1,078
Outstanding at December 31, 2012, Weighted Average Grant-Date Fair Value	$ 6.66
Granted, Number of Shares	84
Granted, Weighted Average Grant-Date Fair Value	$ 6.01
Exercised or released, Number of Shares	(70)
Exercised or released, Weighted Average Grant-Date Fair Value	$ 6.83
Expired or canceled, Number of Shares	(8)
Expired or canceled, Weighted Average Grant-Date Fair Value	$ 7.24
Outstanding at March 31, 2013, Number of Shares	1,084
Outstanding at March 31, 2013, Weighted Average Grant-Date Fair Value	$ 6.59

Share based compensation arrangement by share based payment award options vested and exercisable number.

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- Definition

Share based compensation arrangements by share based payment award options vested and exercised weighted average exercise price.

+ References

No definition available.

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- Definition

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

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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

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-Topic 718

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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- Definition

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

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan 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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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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- Definition

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

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No definition available.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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Number of share options (or share units) exercised during the current period.

+ References

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

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-Name Accounting Standards Codification

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