Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019
Estimated tax benefit (provision)
Beginning balance	$ 1	$ 11
Other comprehensive income (loss) before reclassifications	115	(284)
Less: Amount reclassified from accumulated other comprehensive income	96	(281)
Net current period other comprehensive income (loss)	19	(3)
Ending balance	20	8
AOCI, after tax
Beginning balance	608,693	627,552
Other comprehensive income (loss) before reclassifications	(493)	1,054
Less: Amount reclassified from accumulated other comprehensive income	(360)	1,057
Net current period other comprehensive income (loss)	(133)	(3)
Ending balance	646,267	622,138
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	(608)	1,322
Less: Amount reclassified from accumulated other comprehensive income	(456)	1,338
Net current period other comprehensive income (loss)	(152)	(16)
Ending balance	(130)	(24)
AOCI
AOCI, after tax
Beginning balance	21	(15)
Ending balance	$ (112)	$ (18)

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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