Net Income (Loss) Per Share - Schedule of Basic and Diluted Net Loss Per Share (Detail) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Weighted average common shares outstanding (in shares)	53,238	51,913	52,865	51,799
Less: Unvested common shares subject to repurchase (in shares)	(81)	(32)	(76)	(34)
Total common shares-basic (in shares)	53,157	51,881	52,789	51,765
Stock awards (in shares)	591	53	0	0
Restricted stock awards and units (in shares)	236	138	0	0
Total common shares-diluted (in shares)	53,984	52,072	52,789	51,765

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic).

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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-Glossary Weighted-Average Number of Common Shares Outstanding

-URI http://asc.fasb.org/extlink&oid=6528421

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