v3.20.4

Pension And Postretirement Benefits (Schedule Of Defined Benefit Plan Targeted And Actual Plan Asset Allocations) (Details) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Pension Assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 100.00% | 100.00%
Pension Assets | Domestic |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 19.00% | 17.00%
Pension Assets | Domestic | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 16.00% |
Pension Assets | Domestic | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 26.00% |
Pension Assets | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 15.00% | 12.00%
Pension Assets | International | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 10.00% |
Pension Assets | International | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 20.00% |
Pension Assets | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 35.00% | 35.00%
Pension Assets | Fixed income securities | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 37.00% |
Pension Assets | Fixed income securities | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 47.00% |
Pension Assets | Real estate and real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 8.00% | 9.00%
Pension Assets | Real estate and real assets | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 8.00% |
Pension Assets | Real estate and real assets | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 18.00% |
Pension Assets | Private equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 9.00% | 8.00%
Pension Assets | Private equity | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 5.00% |
Pension Assets | Private equity | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 15.00% |
Pension Assets | Preferred interest |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 10.00% | 17.00%
Pension Assets | Preferred interest | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 6.00% |
Pension Assets | Preferred interest | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 16.00% |
Pension Assets | Other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 4.00% | 2.00%
Pension Assets | Other | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% |
Pension Assets | Other | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 5.00% |
Postretirement (VEBA) Assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 100.00% | 100.00%
Postretirement (VEBA) Assets | Domestic |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 19.00% | 20.00%
Postretirement (VEBA) Assets | Domestic | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 14.00% |
Postretirement (VEBA) Assets | Domestic | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 24.00% |
Postretirement (VEBA) Assets | International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 14.00% | 12.00%
Postretirement (VEBA) Assets | International | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 9.00% |
Postretirement (VEBA) Assets | International | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 19.00% |
Postretirement (VEBA) Assets | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 45.00% | 52.00%
Postretirement (VEBA) Assets | Fixed income securities | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 40.00% |
Postretirement (VEBA) Assets | Fixed income securities | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 50.00% |
Postretirement (VEBA) Assets | Real estate and real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 1.00% | 1.00%
Postretirement (VEBA) Assets | Real estate and real assets | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% |
Postretirement (VEBA) Assets | Real estate and real assets | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 6.00% |
Postretirement (VEBA) Assets | Private equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 1.00% | 2.00%
Postretirement (VEBA) Assets | Private equity | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% |
Postretirement (VEBA) Assets | Private equity | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 6.00% |
Postretirement (VEBA) Assets | Preferred interest |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% | 0.00%
Postretirement (VEBA) Assets | Preferred interest | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% |
Postretirement (VEBA) Assets | Preferred interest | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 0.00% |
Postretirement (VEBA) Assets | Other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 20.00% | 13.00%
Postretirement (VEBA) Assets | Other | Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 15.00% |
Postretirement (VEBA) Assets | Other | Maximum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Actual plan asset allocation percentage | 25.00% |

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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/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 + Details
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