Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 02, 2015	Jan. 03, 2014	Dec. 28, 2012
Net income	$ 40,701us-gaap_NetIncomeLoss	$ 38,640us-gaap_NetIncomeLoss	$ 37,225us-gaap_NetIncomeLoss
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of tax of $304, $(187), and $(184), respectively	(1,017)	373	249
Unrealized gain (loss) arising during the period on investments, net of tax of $(3), $10, and $19, respectively	4	(14)	(28)
Comprehensive income	$ 39,688us-gaap_ComprehensiveIncomeNetOfTax	$ 38,999us-gaap_ComprehensiveIncomeNetOfTax	$ 37,446us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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