Class of Warrant or Right, Outstanding, as a Percentage of Outstanding Common Stock

No definition available.

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- Definition

Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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-Name Accounting Standards Codification

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- Definition

Number of warrants or rights outstanding.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

+ References

No definition available.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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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.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ 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).

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

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

+ References

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- Definition

Price of a single share of a number of saleable stocks of a company.

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- Definition

Number of new stock issued during the period.

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Stockholders' Equity, Equity Incentive Plans and Warrants (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 15, 2009	May 05, 2014	Jan. 31, 2008	May 02, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock, outstanding	9,952,944	9,850,498
Total unrecognized share-based compensation cost	$ 5.2
Unrecognized compensation cost, period for recognition	2 years 6 months
Options granted, weighted average exercise price	$ 2.35	$ 1.05	$ 0.89
Intrinsic value of options exercised	2.6	0.2	0
Fair value of options vested in period	2.9	2.2	2.1
Cash received from exercise of stock options	2.6	0.3	0
Share price	$ 4.42us-gaap_SharePrice
Number of warrants issued as a percentage of outstanding shares						3.50%
Warrants, exercise price						2.40
2000 EIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term	10 years
Common stock reserved for future issuance (in shares)				7,112,217
Options to purchase common stock, outstanding	2,178,746
2009 EIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term	7 years
Common stock reserved for future issuance (in shares)	7,814,281			4,500,000	7,000,000		8,000,000
Options to purchase common stock, outstanding	7,124,198
2000 NEDSOP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Term	10 years
2000ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term	6 months	6 months	6 months
Stock Issued During Period, Shares, New Issues				4,000,000
Shares issued in period	195,857	808,761
Cash received from exercise of stock options	1.1	0.7	0.7
2014ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock, outstanding	3,803,519
Stock Issued During Period, Shares, New Issues					4,000,000
Discount from market price on share purchases	85.00%
Shares issued in period	196,481
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	55,900	92,811
Options outstanding, weighted average exercise price	$ 4.32	$ 1.74	$ 1.23
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 0.3	$ 1.3	$ 3.3
Restricted Stock [Member] \| 2000 EIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0
Restricted Stock [Member] \| 2009 EIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	55,900
Performance Shares [Member] \| 2009 EIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0
Director [Member] \| 2000 NEDSOP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock, outstanding	650,000
Percentage of awards vesting	25.00%
Award vesting period	4 years
Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance	1,000,000
Number of shares available for grant	243,124
Director [Member] \| Vesting after first year [Member] \| 2000 NEDSOP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants outstanding						1,602,489