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Accumulated Other Comprehensive Income (Tables) | 3 Months Ended
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Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Abstract] |
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | The following table shows changes in accumulated other comprehensive income (loss) by component for the three month periods ended March 31, 2018 and 2017:
|  | Unrealized Gains and Losses on Available-for-Sale Securities (1) |  | Unrealized Gains and Losses on Pension Plan Liability (1) |  | Total (1)
Three months ended March 31, 2018 |  | (in thousands)
Beginning balance |  | $ | (19,779 | ) |  | $ | (2,446 | ) |  | $ | (22,225 | )
Adjustment pursuant to adoption of ASU 2016-01 |  | 157 |  |  | — |  |  | 157 |
Other comprehensive loss before reclassifications |  | (26,048 | ) |  | — |  |  | (26,048 | )
Amounts reclassified from accumulated other comprehensive loss |  | (78 | ) |  | 61 |  |  | (17 | )
Net current-period other comprehensive income (loss) |  | (26,126 | ) |  | 61 |  |  | (26,065 | )
Ending balance |  | $ | (45,748 | ) |  | $ | (2,385 | ) |  | $ | (48,133 | )
Three months ended March 31, 2017 |  |  |  |  |  |
Beginning balance |  | $ | (12,704 | ) |  | $ | (6,295 | ) |  | $ | (18,999 | )
Other comprehensive income before reclassifications |  | 1,702 |  |  | 4,604 |  |  | 6,306 |
Amounts reclassified from accumulated other comprehensive income |  | — |  |  | 87 |  |  | 87 |
Net current-period other comprehensive income |  | 1,702 |  |  | 4,691 |  |  | 6,393 |
Ending balance |  | $ | (11,002 | ) |  | $ | (1,604 | ) |  | $ | (12,606 | )
__________ (1) All amounts are net of tax. Amounts in parenthesis indicate debits.
Schedule of reclassifications from accumulated other comprehensive income [Table Text Block] | The following table shows details regarding the reclassifications from accumulated other comprehensive income (loss) for the three month periods ended March 31, 2018 and 2017:
|  | Amount Reclassified from Accumulated Other Comprehensive Income (Loss) |  |
|  | Three Months Ended March 31, |  | Affected line Item in the Consolidated
|  | 2018 |  | 2017 |  | Statement of Income
|  | (in thousands) |  |
Unrealized gains and losses on available-for-sale securities |  |  |  |  |  |
Investment securities gains |  | $ | 102 |  |  | $ | — |  |  | Investment securities gains, net
|  | 102 |  |  | — |  |  | Total before tax
|  | (24 | ) |  | — |  |  | Income tax provision
|  | $ | 78 |  |  | $ | — |  |  | Net of tax
Amortization of pension plan liability |  |  |  |  |  |
Actuarial losses |  | $ | (80 | ) |  | $ | (136 | ) |  | Compensation and employee benefits
|  | (80 | ) |  | (136 | ) |  | Total before tax
|  | 19 |  |  | 49 |  |  | Income tax benefit
|  | $ | (61 | ) |  | $ | (87 | ) |  | Net of tax

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- Definition Accumulated Other Comprehensive Income (Loss) [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss). + References No definition available. + Details
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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