Accumulated Other Comprehensive Income (Summary Of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 5,589
Total change in hedge fair value recorded in Other Comprehensive Income	(243)
Amounts reclassified from accumulated other comprehensive income	29
Net change related to derivatives	(214)	$ (69)
Net current-period other comprehensive income	(15,879)
Balance	(10,290)
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	8,118
Net current-period other comprehensive income	(15,698)
Balance	(7,580)
Unrealized Gain (Losses) On Available-For-Sale Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	10
Net current-period other comprehensive income	(19)
Balance	(9)
Accrued Pension Service Costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(2,287)
Total change in hedge fair value recorded in Other Comprehensive Income
Other comprehensive income before reclassifications
Amounts reclassified from accumulated other comprehensive income
Net change related to derivatives
Net current-period other comprehensive income	52
Balance	(2,235)
Hedge Accounting Reserve [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(252)
Total change in hedge fair value recorded in Other Comprehensive Income	(243)
Amounts reclassified from accumulated other comprehensive income	29
Net change related to derivatives	(214)
Net current-period other comprehensive income	(214)
Balance	$ (466)

Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Net Of Tax

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Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Before Reclassification

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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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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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