Summary of Changes in Product Warranties (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Schedule Of Product Warranty Liability [Line Items]
Balance as of December 31, 2011	$ 6,334
Accruals for warranties issued during the period	998
Adjustments to pre-existing accruals (including changes in estimates)	(470)
Warranty liabilities assumed in SandForce acquisition	426
Settlements made during the period (in cash or in kind)	(1,234)
Balance as of September 30, 2012	$ 6,054

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

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Liability for a standard product warranty acquired in a business acquisition. Does not include any liability for an extended warranty acquired in a business acquisition.

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Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

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Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

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Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

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