Supplemental Disclosure of Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 03, 2015	Apr. 04, 2014
Cash paid during period:
Income taxes	$ 390us-gaap_IncomeTaxesPaid	$ 428us-gaap_IncomeTaxesPaid
Non-cash investing and financing activities:
Unrealized (loss) gain on short-term investments	(7)	14
Vested stock unit awards issued to settle accrued bonuses	6,169	6,008
Stock repurchases payable to broker	$ 0us-gaap_LiabilitiesAssumed1	$ 800us-gaap_LiabilitiesAssumed1

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Vested Restricted Stock Awards Issued to Settle Accrued Bonuses

+ References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

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- Definition

The fair value of liabilities assumed in noncash investing or financing activities.

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- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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