Shareholders' Equity - Summary of Shares of Common Stock Reserved for Future Issuance under Plans (Detail)	Mar. 31, 2014	Dec. 31, 2013
Common Stock Number Of Shares Par Value And Other Disclosures [Abstract]
Stock options outstanding	1,652,867	1,515,621
Restricted stock units outstanding	126,399
Stock options available for future grant	884,578
Common stock reserved for future issuance	2,663,844

Stock options available for future grant.

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Aggregate number of common shares reserved for future issuance.

+ References

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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-Name Accounting Standards Codification

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

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