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Retirement Plans (Weighted-Average Actuarial Assumptions Used To Determine Benefit Expense) (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Pension [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discount rate for benefit obligations | 3.26% | 4.23% | 3.62%
Discount rate for interest on benefit obligations | 2.89% | 3.94% | 3.27%
Discount rate for service cost | 3.42% | 4.33% | 3.77%
Discount rate for interest on service cost | 3.36% | 4.30% | 3.72%
Expected return on plan assets - expense | 7.00% | 7.00% | 7.00%
Compensation increase - expense | 4.10% | 4.10% | 4.19%
OPEB [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Discount rate for benefit obligations | 3.14% | 3.79% | 3.54%
Discount rate for interest on benefit obligations | 2.68% | 3.40% | 3.14%
Discount rate for service cost | 3.21% | 3.92% | 3.71%
Discount rate for interest on service cost | 3.14% | 3.85% | 3.64%
Health care cost trend rate for next year (employees under 65) - expense | 5.64% | 5.87% | 6.09%
Ultimate health care cost trend rate - expense | 4.50% | 4.50% | 4.50%
Year ultimate trend rate reached - expense | 2038 | 2038 | 2038

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- Definition The assumed health care cost trend rate used to measure the expected cost of benefits covered by the plan (gross eligible charges) for employees under age 65. This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money. + References No definition available. + Details
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- Definition The intetest rate used to adjust for the time value of money. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money. + References No definition available. + Details
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- Definition Year the ultimate health care cost trend rate is expected to be reached, in CCYY format. + References No definition available. + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920 + Details
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- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Details
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- Details
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