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Pension Plans And Other Postretirement Benefit Plans (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of Service Related Net Periodic Benefit Costs Capitalized to Utility Property |  |  | 40.00% |
Percentage of Service Related Net Periodic Benefit Costs Recorded to Operating Expenses |  |  | 60.00% |
Percentage of Non-service Related Net Periodic Benefit Costs Capitalized to Regulatory Assets |  |  | 40.00% |
Percentage of Non-service Related Net Periodic Benefit Costs Recorded to Other Expense |  |  | 60.00% |
Pension Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | $ 4,948 | $ 5,318 | $ 14,770 | $ 16,218
Interest cost | 7,134 | 6,634 | 21,372 | 19,566
Expected return on plan assets | (7,913) | (8,101) | (23,681) | (24,601)
Amortization of prior service cost | 75 | 71 | 225 | 221
Net loss recognition | 2,553 | 1,761 | 7,394 | 5,691
Net periodic benefit cost | 6,797 | 5,683 | 20,080 | 17,095
Other Post-Retirement Benefits [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 754 | 815 | 2,279 | 2,423
Interest cost | 1,140 | 1,261 | 3,676 | 3,655
Expected return on plan assets | (616) | (550) | (1,945) | (1,550)
Amortization of prior service cost | (275) | (299) | (825) | (905)
Net loss recognition | 1,299 | 1,044 | 3,874 | 3,261
Net periodic benefit cost | $ 2,302 | $ 2,271 | $ 7,059 | $ 6,884

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit 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 (h)(4) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: 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=112275985&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit 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=112275985&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 (h)(5) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(5) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit 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=112275985&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 (h)(3) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2709-114920 + Details
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