Stockholders' Equity (Schedule Of Changes in Accumulated Other Comprehensive Income by Component Net of Tax) (Details) - USD ($) $ in Thousands	9 Months Ended
	Oct. 02, 2016	Sep. 27, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 3	$ 38
Other comprehensive income (loss) before reclassifications	(619)	(1,278)
Amounts reclassified from accumulated other comprehensive income	858	1,197
Net current period other comprehensive income (loss)	239	(81)
Ending balance	242	(43)
Gain and losses on available for sale securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(40)	(5)
Other comprehensive income (loss) before reclassifications	65	21
Amounts reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	65	21
Ending balance	25	16
Gains and losses on derivatives [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	43	43
Other comprehensive income (loss) before reclassifications	(684)	(1,299)
Amounts reclassified from accumulated other comprehensive income	858	1,197
Net current period other comprehensive income (loss)	174	(102)
Ending balance	$ 217	$ (59)