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Employee Benefits - Components of Net Periodic Pension Cost and Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Components of Net Periodic Pension Cost |  |  |
Interest cost on projected benefit obligation | $ 3,987 | $ 3,882 | $ 4,100
Expected return on plan assets | (4,731) | (6,266) | (6,313)
Amortization of prior service credit - DNB merger | 7 | 0 | 0
Recognized net actuarial loss | 1,604 | 2,134 | 1,866
Net Periodic Pension Expense | 867 | (250) | (347)
Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) |  |  |
Net actuarial loss/(gain) | 2,370 | (3,271) | 3,678
Recognized net actuarial loss | (1,604) | (2,134) | (1,866)
Recognized prior service credit | 0 | 0 | 0
Total (Before Tax Effects) | 766 | (5,405) | 1,812
Total Recognized in Net Benefit Cost and Other Comprehensive Income/(Loss) (Before Tax Effects) | $ 1,633 | $ (5,655) | $ 1,465

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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=118255775&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=118257860&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=118255775&loc=d3e2709-114920 + Details
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