Employee service share based compensation nonvested awards compensation cost expected to be recognized year four.

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Employee service share based compensation nonvested awards compensation cost expected to be recognized year one.

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- Definition

Employee service share based compensation nonvested awards compensation cost expected to be recognized year three.

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- Definition

Employee service share based compensation nonvested awards compensation cost expected to be recognized year two.

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- Definition

Number of stock based compensation plan.

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Percentage of common stock shares beginning.

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Percentage of common stock shares ending.

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Percentage of salary to purchase common stock maximum.

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Restricted common stock vested percentage.

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Restricted common stock vesting period.

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Share based compensation arrangement by share based payment award award vesting percentage.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options exercised in period weighted average.

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- Definition

Share based compensation arrangement by share based payment award first vesting period after grant date.

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- Definition

Share based compensation arrangement by share based payment award granted vesting period after grant date.

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- Definition

Share based compensation arrangement by share based payment award maximum number of shares per employee amount.

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- Definition

Share based compensation arrangement by share based payment award non employee directors vesting period.

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- Definition

Stock option contractual term.

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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-Section 50

-Paragraph 1

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

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- Definition

The amount of expense, net of income tax, 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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- Definition

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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- 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

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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- 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 highest quantity of shares an employee can purchase under the plan per period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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- Definition

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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- Definition

As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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No definition available.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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Stock-Based Compensation (Details Textual) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Plan	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Stock-Based Compensation (Textual) [Abstract]
Stock-based compensation expense	$ 4,167	$ 4,772	$ 6,302
Stock option contractual terms	10 years
Grant date fair value per share	$ 3.24	$ 2.64	$ 4.65
Number of restricted stock awards granted under incentive plan	415,000	211,000
Remaining common stock shares	2,815,000	2,009,000	1,858,000	1,773,000
Common stock purchased under ESPP	110,000	94,000	51,000
Stock option awards granted, options	1,617,000	1,830,000	1,550,000
Share Based Compensation (Additional Textual) [Abstract]
Stock option vesting period	4 years
Stock option granting period after granted	1 year
Vesting period after grant date	4 years
Stock option granted to non employee directors	1 year
Unrecognized compensation cost	6,272
Restricted Common stock Fully vested period	4 years
Restricted Common stock vested Percentage	25.00%
Recognized cost, 2013	2,959
Recognized cost, 2014	2,010
Recognized cost, 2015	1,148
Recognized cost, 2016	155
Number of stock based Compensation Plan	2
Incentive Plan [Member]
Stock-Based Compensation (Textual) [Abstract]
Stock-based compensation expense	4,010	4,589	5,961
Stock option awards granted in percentage	25.00%	25.00%
Intrinsic value of stock options exercised under Incentive Plan	877	374	1,169
Weighted average contractual life of stock option awards exercisable under incentive plan	5 years 8 months 12 days
Aggregate intrinsic value of stock option Exercisable under stock incentive plan	163
Fair value of stock option awards vested under Incentive Plan	3,373	4,775	4,441
Number of stock option awards vested and expected to vest	7,535,000
Weighted average exercise price of stock option awards	$ 6.18
Weighted average remaining contractual life	6 years 1 month 6 days
ESPP [Member]
Stock-Based Compensation (Textual) [Abstract]
Stock-based compensation expense	157	146	192
Weighted average grant date fair value per share under ESPP	$ 1.48	$ 1.33	$ 2.76
Common stock shares reserved	975,000
Remaining common stock shares	177,000
Percentage of salary to purchase common stock	15.00%
Percentage of common stock shares Beginning	85.00%
Percentage of common stock shares Ending	85.00%
Purchase of common stock shares	3
Maximum number of shares per employee amount	$ 25
Common stock purchased under ESPP	110,000	94,000	51,000
Weighted average exercise price of stock issued under ESPP	$ 2.93	$ 3.21	$ 5.50
Compensation expense related to ESPP	157	146	192
Inducement grant [Member]
Stock-Based Compensation (Textual) [Abstract]
Stock-based compensation expense		$ 37	$ 149