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Employee Benefit Plans (Plan's Target Asset Allocation And Actual Asset Allocation) (Details)	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	98.00%
Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Actual Allocation	0.00%	4.20%
Cash Equivalents [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		0.00%
Cash Equivalents [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		20.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	28.25%
Actual Allocation	31.75%	46.10%
Equity Securities [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		40.00%
Equity Securities [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		60.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	59.75%
Actual Allocation	57.65%	45.80%
Fixed Income Securities [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		40.00%
Fixed Income Securities [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		60.00%
Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	12.00%
Actual Allocation	10.60%
Other Financial Instruments [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation		3.90%
Other Financial Instruments [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		0.00%
Other Financial Instruments [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation		5.00%

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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=118257860&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=118255775&loc=d3e1928-114920

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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=118255775&loc=d3e1928-114920

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