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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, 2016 | Dec. 31, 2015
Cash And Cash Equivalents [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation, Minimum | 0.00% |
Target Allocation, Maximum | 20.00% |
Percentage of Plan Assets | 6.10% | 5.20%
Weighted Average Expected Long-term Rate of Return | 0.18% |
Equity Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation, Minimum | 40.00% |
Target Allocation, Maximum | 60.00% |
Percentage of Plan Assets | 47.90% | 47.20%
Weighted Average Expected Long-term Rate of Return | 3.89% |
Fixed Income Securities [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation, Minimum | 40.00% |
Target Allocation, Maximum | 60.00% |
Percentage of Plan Assets | 42.60% | 43.90%
Weighted Average Expected Long-term Rate of Return | 2.14% |
Other Financial Instruments [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target Allocation, Minimum | 0.00% |
Target Allocation, Maximum | 5.00% |
Percentage of Plan Assets | 3.40% | 3.70%
Weighted Average Expected Long-term Rate of Return | 0.26% |

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- Definition Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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