Stock-Based Compensation (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Options
Stock-Based Compensation
Unamortized compensation cost, net of expected forfeitures	$ 3,900,000
Weighted average expected period over which the expense is to be recognized	2 years 4 months 24 days
Tax benefits associated with exercise of stock options	0	0
Inducement grant options
Number of Shares
Balance at the end of the year (in shares)	2,233,000
Weighted Average Exercise Prices
Balance at the end of the year (in dollars per share)	$ 3.68
RSU's
Stock-Based Compensation
Weighted average expected period over which the expense is to be recognized	2 years
Unamortized compensation cost for awards other than options, net of expected forfeitures	$ 900,000
RSU's \| Minimum
Stock-Based Compensation
Stock-based compensation expense, recognition period	3 years
RSU's \| Maximum
Stock-Based Compensation
Stock-based compensation expense, recognition period	5 years
Plans \| Options
Available for Grant
Balance at the beginning of the year (in shares)	1,760,000
Additional shares authorized under the Amended 2010 Plan	500,000
Restricted stock units cancelled (in shares)	(6,000)
Options granted (in shares)	(1,323,000)
Options cancelled (in shares)	153,000
Options expired (in shares)	(78,000)
Balance at the end of the year (in shares)	1,018,000
Number of Shares
Balance at the beginning of the year (in shares)	5,994,000
Options granted (in shares)	(1,323,000)
Options cancelled (in shares)	(153,000)
Options exercised (in shares)	(22,000)
Balance at the end of the year (in shares)	7,142,000
Weighted Average Exercise Prices
Balance at the beginning of the year (in dollars per share)	$ 3.87
Options granted (in dollars per share)	$ 2.05
Options cancelled (in dollars per share)	$ 5.00
Options exercised (in dollars per share)	$ 1.60
Options expired (in dollars per share)	$ 5.79
Balance at the end of the year (in dollars per share)	$ 3.52
Plans \| RSU's
Available for Grant
Restricted stock units cancelled (in shares)	6,000

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

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Number of additional shares authorized for issuance under an established share-based compensation 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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Gross 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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of share instruments newly issued under a share-based compensation plan.

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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 of the plan that expired.

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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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