Stockholders' Equity (Schedule Of Changes in Accumulated Other Comprehensive Income by Component) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 01, 2017	Oct. 02, 2016	Oct. 01, 2017	Oct. 02, 2016
Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
Other comprehensive income (loss), before tax	$ 63	$ 197	$ (7,719)	$ 308
Accumulated Other Comprehensive Income (Loss), Tax [Roll Forward]
AOCI Tax (Beginning)			(261)	24
Other comprehensive income (loss) before reclassification, Tax			2,038	393
Amount reclassified from AOCI, Tax			1,019	462
Other comprehensive income (loss), Tax			1,019	(69)
AOCI Tax (Ending)	758	(45)	758	(45)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI, Net of Tax (Beginning)			1,938	3
Other comprehensive loss before reclassifications			(8,593)	(619)
Amount reclassified from accumulated other comprehensive income			(1,893)	(858)
Net current period other comprehensive income (loss)			(6,700)	239
AOCI, Net of Tax (Ending)	(4,762)	242	(4,762)	242
Unrealized gains (losses) on available for sale securities [Member]
Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
AOCI before Tax (Beginning)			(31)	(64)
Other comprehensive income (loss), before reclassification, before Tax			(41)	104
Amount reclassified from AOCI, before Tax			0	0
Other comprehensive income (loss), before tax			(41)	104
AOCI before Tax (Ending)	(72)	40	(72)	40
Unrealized gains (losses) on derivatives [Member]
Accumulated Other Comprehensive Income (Loss), Before Tax [Roll Forward]
AOCI before Tax (Beginning)			2,230	43
Other comprehensive income (loss), before reclassification, before Tax			(10,590)	(1,116)
Amount reclassified from AOCI, before Tax			(2,912)	(1,320)
Other comprehensive income (loss), before tax			(7,678)	204
AOCI before Tax (Ending)	$ (5,448)	$ 247	$ (5,448)	$ 247

Accumulated Other Comprehensive Income (Loss), Before Tax [ Roll Forward] [Roll Forward]

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Accumulated Other Comprehensive Income (Loss), Tax [Roll Froward] [Roll Forward]

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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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 accumulated other comprehensive income (loss) attributable to parent.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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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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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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