Supplemental Disclosure of Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 02, 2015	Jan. 03, 2014	Dec. 28, 2012
Cash paid during period:
Income taxes	$ 27,421us-gaap_IncomeTaxesPaid	$ 24,701us-gaap_IncomeTaxesPaid	$ 24,104us-gaap_IncomeTaxesPaid
Non-cash investing and financing activities:
Unrealized gain (loss) on investments	4	(14)	(28)
Vested stock unit awards granted to settle accrued bonus	6,008	5,807	5,343
Stock repurchases payable to broker	$ 0us-gaap_LiabilitiesAssumed1	$ 0us-gaap_LiabilitiesAssumed1	$ 508us-gaap_LiabilitiesAssumed1

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Vested Restricted Stock Awards Issued to Settle Accrued Bonuses

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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.

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

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

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