Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2018	Apr. 02, 2017
Estimated tax benefit (provision)
Beginning balance	$ 133	$ (261)
Other comprehensive income (loss) before reclassifications	388	(337)
Less: Amount reclassified from accumulated other comprehensive income	460	(553)
Net current period other comprehensive income (loss)	(72)	216
Ending balance	61	(45)
AOCI, after tax
Beginning balance	730,485
Other comprehensive income (loss) before reclassifications	(1,150)	(509)
Amount reclassified from accumulated other comprehensive income, Net of tax	(1,732)	1,027
Less: Amount reclassified from accumulated other comprehensive income	582	(1,536)
Ending balance	755,719
Unrealized gains (losses) on available-for-sale securities
AOCI, before tax
Beginning balance	(146)	(31)
Other comprehensive income (loss) before reclassifications	(38)	(55)
Less: Amount reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	(38)	(55)
Ending balance	(184)	(86)
Unrealized gains (losses) on derivatives
AOCI, before tax
Beginning balance	(838)	2,230
Other comprehensive income (loss) before reclassifications	(1,500)	(117)
Less: Amount reclassified from accumulated other comprehensive income	(2,192)	1,580
Net current period other comprehensive income (loss)	692	(1,697)
Ending balance	(146)	533
Total
AOCI, after tax
Beginning balance	(851)	1,938
Ending balance	$ (269)	$ 402