Note 8 - Accumulated Other Comprehensive Income (Details) - Changes in Accumulated Other Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 27, 2014		Sep. 28, 2013		Sep. 27, 2014		Sep. 28, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income			$ 1,964		$ 1,647		$ 2,052
Other comprehensive income before reclassifications			(55)		81		1,305
Amounts reclassified from accumulated other comprehensive income
Net current period other comprehensive income			(80)		(1,647)		(168)
Accumulated other comprehensive income			1,884				1,884
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income		[1]	(25)	[1]	(1,728)	[1]	(1,476)	[1]
Accumulated Translation Adjustment [Member]
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income							$ 3

[1] Amounts reclassified are recorded within Other income, net in the Condensed Consolidated Statements of Operations.