Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 27, 2021	Jun. 28, 2020
Estimated tax benefit (provision)
Beginning balance	$ 9	$ 1
Other comprehensive income (loss) before reclassifications	154	(196)
Less: Amount reclassified from accumulated other comprehensive income (loss)	171	(197)
Net current period other comprehensive income (loss)	(17)	1
Ending balance	(8)	2
AOCI, after tax
Beginning balance	689,384	608,693
Other comprehensive income (loss) before reclassifications	(525)	726
Less: Amount reclassified from accumulated other comprehensive income (loss)	(642)	740
Net current period other comprehensive income (loss)	117	(14)
Ending balance	723,000	606,146
Unrealized gains (losses) on available-for-sale investments
AOCI, before tax
Beginning balance	(2)	(2)
Other comprehensive income (loss) before reclassifications	0	0
Less: Amount reclassified from accumulated other comprehensive income (loss)	0	0
Net current period other comprehensive income (loss)	0	0
Ending balance	(2)	(2)
Unrealized gains (losses) on derivatives
AOCI, before tax
Beginning balance	(42)	22
Other comprehensive income (loss) before reclassifications	(679)	922
Less: Amount reclassified from accumulated other comprehensive income (loss)	(813)	937
Net current period other comprehensive income (loss)	134	(15)
Ending balance	92	7
AOCI
AOCI, after tax
Beginning balance	(35)	21
Ending balance	$ 82	$ 7

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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