Stockholders' Equity (Schedule of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2020	Mar. 31, 2019
Estimated tax benefit (provision)
Beginning balance	$ 1	$ 11
Other comprehensive income (loss) before reclassifications	(175)	(73)
Less: Amount reclassified from accumulated other comprehensive income	(122)	(64)
Net current period other comprehensive income (loss)	(53)	(9)
Ending balance	(52)	2
AOCI, after tax
Beginning balance	608,693	627,552
Other comprehensive income (loss) before reclassifications	810	271
Less: Amount reclassified from accumulated other comprehensive income	460	242
Net current period other comprehensive income (loss)	350	29
Ending balance	597,791	632,908
Unrealized gains (losses) on available-for-sale investments
AOCI, before tax
Beginning balance	(2)	(18)
Other comprehensive income (loss) before reclassifications	0	15
Less: Amount reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive income (loss)	0	15
Ending balance	(2)	(3)
Unrealized gains (losses) on derivatives
AOCI, before tax
Beginning balance	22	(8)
Other comprehensive income (loss) before reclassifications	985	329
Less: Amount reclassified from accumulated other comprehensive income	582	306
Net current period other comprehensive income (loss)	403	23
Ending balance	425	15
AOCI
AOCI, after tax
Beginning balance	21	(15)
Ending balance	$ 371	$ 14

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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