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Stock Options Granted To Employees And Non-Employees (Detail) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Number of Options Granted	687,183	454,014
Exercise Price	$ 3.19	$ 0.94
Options granted on 01/08/2012
Grant Date	Jan. 08, 2012
Number of Options Granted	112,881
Exercise Price	$ 0.94
Estimated Option Fair Value	$ 0.56
Intrinsic Value
Options granted on 03/14/2012
Grant Date	Mar. 14, 2012
Number of Options Granted	313,094
Exercise Price	$ 0.94
Estimated Option Fair Value	$ 0.56
Intrinsic Value
Options granted on 06/13/2012
Grant Date	Jun. 13, 2012
Number of Options Granted	4,314
Exercise Price	$ 0.94
Estimated Option Fair Value	$ 0.56
Intrinsic Value
Options granted on 09/19/2012
Grant Date	Sep. 19, 2012
Number of Options Granted	8,011
Exercise Price	$ 0.94
Estimated Option Fair Value	$ 0.56
Intrinsic Value
Options granted on 11/08/2012
Grant Date	Nov. 08, 2012
Number of Options Granted	15,713
Exercise Price	$ 0.94
Estimated Option Fair Value	$ 0.56
Intrinsic Value
Options granted on 01/06/2013
Grant Date	Jan. 06, 2013
Number of Options Granted	337,282
Exercise Price	$ 1.50
Estimated Option Fair Value	$ 0.94
Intrinsic Value
Options granted on 03/08/2013
Grant Date	Mar. 08, 2013
Number of Options Granted	14,008
Exercise Price	$ 1.50
Estimated Option Fair Value	$ 0.94
Intrinsic Value
Options granted on 06/19/2013
Grant Date	Jun. 19, 2013
Number of Options Granted	59,497
Exercise Price	$ 2.63
Estimated Option Fair Value	$ 1.88
Intrinsic Value
Options granted on 07/19/2013
Grant Date	Jul. 19, 2013
Number of Options Granted	206,083
Exercise Price	$ 4.69
Estimated Option Fair Value	$ 2.95
Intrinsic Value
Options granted on 09/18/2013
Grant Date	Sep. 18, 2013
Number of Options Granted	72,014
Exercise Price	$ 7.51
Estimated Option Fair Value	$ 4.76
Intrinsic Value

X

- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Grant Date

+ References

No definition available.

+ Details

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X

- Definition

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

+ 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 (c)(1)(iv)(1)

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

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X

- Definition

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

+ 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 (d)(1)

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

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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.

+ 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 (d)(1)

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

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X

- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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