Stock-Based Compensation - Summary of Changes in Stock Options Outstanding (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding at December 31, 2012,Weighted-average remaining contractual term	3 years 8 months 1 day
Options exercisable at December 31, 2012,Weighted-average remaining contractual term	2 years 6 months 22 days
Options outstanding at January 1, 2012,Weighted-Average Exercise Price Per Share	$ 6.19
Assumed in SandForce acquisition,Weighted-Average Exercise Price Per Share	$ 0.75
Granted,Weighted-Average Exercise Price Per Share	$ 8.37
Exercised,Weighted-Average Exercise Price Per Share	$ 5.15
Canceled,Weighted-Average Exercise Price Per Share	$ 8.34
Options outstanding at December 31, 2012,Weighted-Average Exercise Price Per Share	$ 5.75
Options exercisable at December 31, 2012,Weighted-Average Exercise Price Per Share	$ 6.08
Options outstanding at January 1, 2012,Number of Shares	64,245
Assumed in SandForce acquisition,Number of Shares	7,542
Granted,Number of Shares	5,479
Exercised,Number of Shares	(15,679)
Canceled,Number of Shares	(5,545)
Options outstanding at December 31, 2012,Number of Shares	56,042
Options exercisable at December 31, 2012,Number of Shares	34,742
Options outstanding at December 31, 2012,Aggregate Intrinsic Value	$ 102,589
Options exercisable at December 31, 2012,Aggregate Intrinsic Value	$ 55,534

Share based compensation arrangement by share based payment award options assumed in acquisition shares.

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Share based compensation arrangement by share based payment award options assumed in acquisition weighted average exercise price per share.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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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.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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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.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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Number of share options (or share units) exercised during the current period.

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