Stock-Based Compensation (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Summary of related activity under Incentive Plan
Awards Available, Beginning balance	2,815
Options Outstanding, Beginning balance	8,073
Weighted Average Exercise Price, Beginning balance	$ 6.09
Restricted stock awards granted, Awards Available	(305)
Restricted stock awards granted, Options Outstanding
Restricted stock awards granted, Weighted Average Exercise Price
Restricted stock awards cancelled, Awards Available	29
Restricted stock awards cancelled, Options Outstanding
Restricted stock awards cancelled, Weighted Average Exercise Price
Stock option awards granted, Awards Available	(2,003)
Stock option awards granted, Options Outstanding	2,003
Stock option awards granted, Weighted Average Exercise Price	$ 1.43
Stock option awards exercised, Awards Available
Stock option awards exercised, Options Outstanding	(307)
Stock option awards exercised, Weighted Average Exercise Price	$ 1.17
Stock option awards cancelled, Awards Available	1,088
Stock option awards cancelled, Options Outstanding	(1,088)
Stock option awards cancelled, Weighted Average Exercise Price	$ 6.02
Awards Available, Ending balance	1,624
Options Outstanding, Ending balance	8,681
Weighted Average Exercise Price, Ending balance	$ 5.20

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Share based compensation arrangement by share based payment award options forfeitures in period awards available.

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Share based compensation arrangement by share based payment award options grants in period awards available.

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Share based compensation arrangement by share based payment award restricted options cancelled outstanding.

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Share based compensation arrangement by share based payment award restricted options cancelled weighted average exercise price.

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Share based compensation arrangement by share based payment award restricted options granted outstanding.

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Share based compensation arrangement by share based payment award restricted options granted weighted average exercise price.

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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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).

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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Number of options outstanding, including both vested and non-vested options.

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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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-Publisher FASB

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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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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-Publisher SEC

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-Number 210

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