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Employee Benefit Plans (Target Allocation, Percentage Of Plan Assets And Weighted Average Expected Rate Of Return) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	4.20%	6.40%
Weighted Average Expected Long-term Rate of Return	0.11%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	46.10%	50.20%
Weighted Average Expected Long-term Rate of Return	3.71%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	45.80%	40.20%
Weighted Average Expected Long-term Rate of Return	2.24%
Other Financial Instruments [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of Plan Assets	3.90%	3.20%
Weighted Average Expected Long-term Rate of Return	0.30%
Minimum [Member] | Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Minimum [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	40.00%
Minimum [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	40.00%
Minimum [Member] | Other Financial Instruments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Maximum [Member] | Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	20.00%
Maximum [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	60.00%
Maximum [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	60.00%
Maximum [Member] | Other Financial Instruments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	5.00%

X

- Definition

Defined benefit plan weighted average expected long term rate of return.

+ References

No definition available.

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- Definition

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+ References

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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