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

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

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Employee stock purchase plan period to purchase common stock.

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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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Share based compensation arranged by share based payment award stock option award pro rata vesting period.

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

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

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

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

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Share based compensation arrangement by share based payment award vesting period description.

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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.

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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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

Unrecognized cost of unvested share-based compensation awards.

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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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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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-Name Accounting Standards Codification

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-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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- Definition

The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

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- Definition

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

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-Name Accounting Standards Codification

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-SubTopic 10

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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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- 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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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

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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-Name Accounting Standards Codification

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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 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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-Name Accounting Standards Codification

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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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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

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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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-Name Accounting Standards Codification

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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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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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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Section S99

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

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Stock-Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 Plan	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 4,368	$ 4,167	$ 4,772
Number of stock based Compensation Plan	2
Stock option award period	3 years
Stock option vesting period	4 years
Stock option granting period after granted	1 year
Grant date fair value per share	$ 1.28	$ 3.24	$ 2.64
Expected dividend Yield	0
Unrecognized compensation cost	4,749
Recognized cost, 2014	2,609
Recognized cost, 2015	1,446
Recognized cost, 2016	580
Recognized cost, 2017	114
Remaining common stock shares	1,082	2,815	2,009	1,858
Common stock purchased under ESPP	89	110	94
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards granted in percentage	50.00%
Performance Based Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based stock options	1,032
Stock-based compensation expense	0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option contractual terms	10 years
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option contractual terms	5 years
Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	4,253	4,010	4,589
Stock option awards granted to nonemployee director vesting period description	Stock option awards granted to non-employee directors of the Company generally vest monthly over one year.
Stock option vesting period	2 years
Stock option contractual terms	4 years 10 months 24 days
Intrinsic value of stock options exercised under Incentive Plan	738	877	374
Aggregate intrinsic value of stock option Exercisable under stock incentive plan	11,189
Fair value of stock option awards vested under Incentive Plan	3,483	3,373	4,775
Number of stock option awards vested and expected to vest	8,146
Weighted average exercise price of stock option awards	$ 5.11
Weighted average remaining contractual life	6 years 7 months 6 days
Incentive Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards granted in percentage	25.00%
ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	115	157	146
Stock-based compensation expense	115	157	146
Common stock shares reserved	975
Remaining common stock shares	88
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
Purchase intervals	6 months
Common stock purchased under ESPP	89	110	94
Weighted average exercise price of stock issued under ESPP	$ 1.39	$ 2.93	$ 3.21
Weighted average grant date fair value per share under ESPP	$ 1.27	$ 1.48	$ 1.33
Inducement Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 37