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Benefit Plans (Allocation Of Plan Assets) (Details) | Dec. 31, 2018
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Pension Plans, Defined Benefit [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 4.00%
Pension Plans, Defined Benefit [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 25.00%
Pension Plans, Defined Benefit [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 22.00%
Pension Plans, Defined Benefit [Member] | Global asset securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 9.00%
Pension Plans, Defined Benefit [Member] | Risk parity securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 10.00%
Pension Plans, Defined Benefit [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 30.00%
Other Postretirement Benefits Plans [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 1.00%
Other Postretirement Benefits Plans [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 24.00%
Other Postretirement Benefits Plans [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 2.00%
Other Postretirement Benefits Plans [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Actual allocation | 73.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 0.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 11.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 14.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Global asset securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 5.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Risk parity securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 5.00%
Minimum [Member] | Pension Plans, Defined Benefit [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 20.00%
Minimum [Member] | Other Postretirement Benefits Plans [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 0.00%
Minimum [Member] | Other Postretirement Benefits Plans [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 0.00%
Minimum [Member] | Other Postretirement Benefits Plans [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 0.00%
Minimum [Member] | Other Postretirement Benefits Plans [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 20.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 5.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 41.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 34.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Global asset securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 15.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Risk parity securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 15.00%
Maximum [Member] | Pension Plans, Defined Benefit [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 40.00%
Maximum [Member] | Other Postretirement Benefits Plans [Member] | Cash and equivalents [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 5.00%
Maximum [Member] | Other Postretirement Benefits Plans [Member] | Equity securites - U.S. [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 46.00%
Maximum [Member] | Other Postretirement Benefits Plans [Member] | Equity securities - international [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 34.00%
Maximum [Member] | Other Postretirement Benefits Plans [Member] | Fixed income securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Target range allocation, percentage | 100.00%

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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + 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) -URI http://asc.fasb.org/extlink&oid=82843861&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)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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