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Pension and Other Postretirement Benefits (Impact on Amounts Reported Due to a 1% Change in the Annual Medical Inflation Rate Issued) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Other Postretirement Benefits [Abstract] |  |
Effect on accumulated postretirement benefit obligation, 1% increase | $ 716 | $ 831
Effect on accumulated postretirement benefit obligation, 1% decrease | (614) | (702)
Effect on annual service and interest costs, 1% increase | 31 | 36
Effect on annual service and interest costs, 1% decrease | $ (26) | $ (30)

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- Definition Other Postretirement Benefits [Abstract]. + References No definition available. + Details
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- Definition Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of increase in accumulated postretirement benefit obligation from one-percentage-point increase in assumed health care cost trend rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of increase in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point increase in assumed health care cost trend rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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