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Pension, Savings, And Other Employee Benefits (Schedule of Amounts Recognized in Other Comprehensive Income) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Pension Benefits |  |
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] |  |
Net actuarial (gain)/loss arising during measurement period | $ 15,357 | $ 24,408
Items amortized during the measurement period: |  |
Prior service credit/(cost) | (52) | (196)
Net actuarial gain/(loss) | (9,521) | (8,141)
Total recognized in other comprehensive income | 5,784 | 16,071
Other Benefits |  |
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] |  |
Net actuarial (gain)/loss arising during measurement period | 2,222 | 2,032
Items amortized during the measurement period: |  |
Prior service credit/(cost) | (95) | (170)
Net actuarial gain/(loss) | 567 | 810
Total recognized in other comprehensive income | $ 2,694 | $ 2,672

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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(4) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit 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 (i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 + Details
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- Definition Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income from prior service cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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