Shareholders' Equity - Summary of Shares of Common Stock Reserved for Future Issuance under Plans (Detail)	Sep. 30, 2013	Dec. 31, 2012
Common Stock Number Of Shares Par Value And Other Disclosures [Abstract]
Stock options outstanding	1,616,763	1,539,618
Restricted stock units outstanding	228,299
Stock options available for future grant	952,724
Common stock reserved for future issuance	2,797,786

Stock options available for future grant reserved for future issuance.

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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.

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

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