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Benefit Plans (Allocation Of Plan Assets) (Details) | 12 Months Ended
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Dec. 31, 2016
Pension Plans, Defined Benefit [Member] | Cash and Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 0.00%
Target range allocation, maximum | 5.00%
Actual allocation | 3.00%
Pension Plans, Defined Benefit [Member] | Equity securites - domestic [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 22.00%
Target range allocation, maximum | 42.00%
Actual allocation | 30.00%
Pension Plans, Defined Benefit [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 8.00%
Target range allocation, maximum | 28.00%
Actual allocation | 17.00%
Pension Plans, Defined Benefit [Member] | Global Asset Allocation Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 5.00%
Target range allocation, maximum | 15.00%
Actual allocation | 10.00%
Pension Plans, Defined Benefit [Member] | Risk Parity Allocation Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 5.00%
Target range allocation, maximum | 15.00%
Actual allocation | 10.00%
Pension Plans, Defined Benefit [Member] | Fixed Income Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 20.00%
Target range allocation, maximum | 40.00%
Actual allocation | 30.00%
Other Postretirement Benefits Plans [Member] | Cash and Equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 0.00%
Target range allocation, maximum | 15.00%
Actual allocation | 3.00%
Other Postretirement Benefits Plans [Member] | Equity securites - domestic [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 0.00%
Target range allocation, maximum | 45.00%
Actual allocation | 22.00%
Other Postretirement Benefits Plans [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 0.00%
Target range allocation, maximum | 21.00%
Actual allocation | 13.00%
Other Postretirement Benefits Plans [Member] | Global Asset Allocation Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 5.00%
Target range allocation, maximum | 40.00%
Actual allocation | 16.00%
Other Postretirement Benefits Plans [Member] | Fixed Income Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, minimum | 10.00%
Target range allocation, maximum | 70.00%
Actual allocation | 46.00%

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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=65897934&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=65897934&loc=d3e1928-114920 + Details
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