v2.4.0.8

Summary of Stock Options Outstanding and Exercisable (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Number of Shares	8,061,491
$1.86-$4.01
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 1.86
Range of Exercise Prices, Upper Limit	$ 4.01
Options Outstanding, Number of Shares	1,391,649
Options Outstanding, Weighted Average Remaining Contractual Life	2 years 9 months 7 days
Options Outstanding, Weighted Average Exercise Price	$ 3.45
Options Exercisable, Number of Shares	1,380,649
Options Exercisable, Weighted Average Exercise Price	$ 3.44
$4.03-$5.09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 4.03
Range of Exercise Prices, Upper Limit	$ 5.09
Options Outstanding, Number of Shares	1,069,881
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 2 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 4.66
Options Exercisable, Number of Shares	964,821
Options Exercisable, Weighted Average Exercise Price	$ 4.69
$5.11-$5.45
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 5.11
Range of Exercise Prices, Upper Limit	$ 5.45
Options Outstanding, Number of Shares	1,038,900
Options Outstanding, Weighted Average Remaining Contractual Life	2 years 11 months 19 days
Options Outstanding, Weighted Average Exercise Price	$ 5.14
Options Exercisable, Number of Shares	1,021,468
Options Exercisable, Weighted Average Exercise Price	$ 5.14
$5.47-$5.65
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 5.47
Range of Exercise Prices, Upper Limit	$ 5.65
Options Outstanding, Number of Shares	1,772,230
Options Outstanding, Weighted Average Remaining Contractual Life	7 years 1 month 28 days
Options Outstanding, Weighted Average Exercise Price	$ 5.51
Options Exercisable, Number of Shares	1,214,970
Options Exercisable, Weighted Average Exercise Price	$ 5.50
$5.66-$6.10
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 5.66
Range of Exercise Prices, Upper Limit	$ 6.10
Options Outstanding, Number of Shares	1,319,309
Options Outstanding, Weighted Average Remaining Contractual Life	4 years 11 months 23 days
Options Outstanding, Weighted Average Exercise Price	$ 6.04
Options Exercisable, Number of Shares	994,693
Options Exercisable, Weighted Average Exercise Price	$ 6.09
$6.12-$6.29
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 6.12
Range of Exercise Prices, Upper Limit	$ 6.29
Options Outstanding, Number of Shares	147,912
Options Outstanding, Weighted Average Remaining Contractual Life	4 years 11 months 9 days
Options Outstanding, Weighted Average Exercise Price	$ 6.22
Options Exercisable, Number of Shares	117,822
Options Exercisable, Weighted Average Exercise Price	$ 6.21
$6.30-$6.30
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 6.30
Range of Exercise Prices, Upper Limit	$ 6.30
Options Outstanding, Number of Shares	1,040,777
Options Outstanding, Weighted Average Remaining Contractual Life	7 years 3 months 15 days
Options Outstanding, Weighted Average Exercise Price	$ 6.30
Options Exercisable, Number of Shares	667,562
Options Exercisable, Weighted Average Exercise Price	$ 6.30
$6.33-$7.91
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 6.33
Range of Exercise Prices, Upper Limit	$ 7.91
Options Outstanding, Number of Shares	280,833
Options Outstanding, Weighted Average Remaining Contractual Life	7 years 8 months 12 days
Options Outstanding, Weighted Average Exercise Price	$ 6.96
Options Exercisable, Number of Shares	155,584
Options Exercisable, Weighted Average Exercise Price	$ 6.79
$1.86-$7.91
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Exercise Prices, Lower Limit	$ 1.86
Range of Exercise Prices, Upper Limit	$ 7.91
Options Outstanding, Number of Shares	8,061,491
Options Outstanding, Weighted Average Remaining Contractual Life	5 years 2 months 27 days
Options Outstanding, Weighted Average Exercise Price	$ 5.25
Options Exercisable, Number of Shares	6,517,569
Options Exercisable, Weighted Average Exercise Price	$ 5.10

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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



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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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Publisher FASB

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

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