Shareholders' Equity (Schedule Of Changes In Equity) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Loss
Accumulated other comprehensive loss	$ (354,409)	$ (269,531)	$ (456,461)	$ (438,436)
Other comprehensive income (loss) before reclassifications	(2,731)	871	481
Other comprehensive income (loss) before reclassifications	0	0	226
Other comprehensive income (loss) before reclassifications	(99,060)	174,240	(29,763)
Amounts reclassified from accumulated other comprehensive loss	14,182	12,690	11,738
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Loss
Accumulated other comprehensive loss	(3,155)	(424)	(1,295)	(1,776)
Amounts reclassified from accumulated other comprehensive loss	0	0	0
Unrealized (Gain) Loss on Available-for-Sale Security
Accumulated Other Comprehensive Loss
Accumulated other comprehensive loss	0	0	0	(226)
Amounts reclassified from accumulated other comprehensive loss	0	0	0
Employee Benefit Plans
Accumulated Other Comprehensive Loss
Accumulated other comprehensive loss	(351,254)	(269,107)	(455,166)	(436,434)
Other comprehensive income (loss) before reclassifications	(96,329)	173,369	(30,470)
Amounts reclassified from accumulated other comprehensive loss	$ 14,182	$ 12,690	$ 11,738

Other Comprehensive Income (Loss), Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)

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- Definition

Other Comprehensive Income (Loss), Amounts Reclassified from Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities

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Other Comprehensive Income (Loss), Amounts Reclassified from Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment

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Other Comprehensive Income (Loss), Amounts Reclassified from Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

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-Name Regulation S-X (SX)

-Number 210

-Section 04

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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

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-SubTopic 10

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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-Subparagraph (a)

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-Topic 830

-SubTopic 30

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-Paragraph 20

-Subparagraph (b,c)

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Amount before tax and reclassification adjustments of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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