Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 28, 2020	Jun. 30, 2019
Estimated tax benefit (provision)
Beginning balance	$ 1	$ 11
Other comprehensive income (loss) before reclassifications	(196)	(187)
Less: Amount reclassified from accumulated other comprehensive income	(197)	(177)
Net current period other comprehensive income (loss)	1	(10)
Ending balance	2	1
AOCI, after tax
Beginning balance	608,693	627,552
Other comprehensive income (loss) before reclassifications	726	692
Less: Amount reclassified from accumulated other comprehensive income	740	665
Net current period other comprehensive income (loss)	(14)	27
Ending balance	606,146	622,072
Unrealized gains (losses) on available-for-sale investments
AOCI, before tax
Beginning balance	(2)	(18)
Other comprehensive income (loss) before reclassifications	0	16
Less: Amount reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	0	16
Ending balance	(2)	(2)
Unrealized gains (losses) on derivatives
AOCI, before tax
Beginning balance	22	(8)
Other comprehensive income (loss) before reclassifications	922	863
Less: Amount reclassified from accumulated other comprehensive income	937	842
Net current period other comprehensive income (loss)	(15)	21
Ending balance	7	13
AOCI
AOCI, after tax
Beginning balance	21	(15)
Ending balance	$ 7	$ 12

Accumulated other comprehensive income (loss), before tax.

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Accumulated other comprehensive income (loss), tax.

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Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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