Pension Plans And Other Post-Retirement Benefits (Schedule Of Effect Of One-Percentage-Point Change In Assumed Health Care Cost Trend Rates) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Pension Plans And Other Post-Retirement Benefits [Abstract]
Effect on the health-care component of the accrued other post-retirement benefit obligation, 1-Percentage- Point Increase	$ 5,131
Effect on the health-care component of the accrued other post-retirement benefit obligation, 1-Percentage- Point Decrease	(4,548)
Effect on aggregate service and interest cost components of net periodic post-retirement health-care benefit cost, 1-Percentage- Point Increase	301
Effect on aggregate service and interest cost components of net periodic post-retirement health-care benefit cost, 1-Percentage- Point Decrease	$ (227)

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- Definition

Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (m)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

+ Details

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- Definition

Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate.

+ References

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- Definition

Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate.

+ References

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Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate.

+ References

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