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Accumulated Other Comprehensive Income (Tables) | 3 Months Ended
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Mar. 31, 2020
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 months ended March 31, 2020 and 2019:
|  | Unrealized Gains and Losses on Available for Sale Securities (1) |  | Unrealized Gains and Losses on Pension Plan Liability (1) |  | Unrealized Gains and Losses on Hedging Instruments (1) |  | Total (1)
Three Months Ended March 31, 2020 |  | (in thousands)
Beginning balance |  | $ | 33,038 |  |  | $ | (3,974 | ) |  | $ | 11,303 |  |  | $ | 40,367 |
Other comprehensive income before reclassifications |  | 79,696 |  |  | — |  |  | 17,977 |  |  | 97,673 |
Amounts reclassified from accumulated other comprehensive income (2) |  | (191 | ) |  | 80 |  |  | (722 | ) |  | (833 | )
Net current-period other comprehensive income |  | 79,505 |  |  | 80 |  |  | 17,255 |  |  | 96,840 |
Ending balance |  | $ | 112,543 |  |  | $ | (3,894 | ) |  | $ | 28,558 |  |  | $ | 137,207 |
Three Months Ended March 31, 2019 |  |  |  |  |  |  |  |
Beginning balance |  | $ | (33,128 | ) |  | $ | (2,177 | ) |  | $ | — |  |  | $ | (35,305 | )
Other comprehensive income before reclassifications |  | 32,063 |  |  | — |  |  | 4,810 |  |  | 36,873 |
Amounts reclassified from accumulated other comprehensive loss (2) |  | 1,417 |  |  | 61 |  |  | — |  |  | 1,478 |
Net current-period other comprehensive income |  | 33,480 |  |  | 61 |  |  | 4,810 |  |  | 38,351 |
Ending balance |  | $ | 352 |  |  | $ | (2,116 | ) |  | $ | 4,810 |  |  | $ | 3,046 |
__________ (1) All amounts are net of tax. Amounts in parenthesis indicate debits. (2) See following table for details about these reclassifications.
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 months ended March 31, 2020 and 2019:
|  | Amount Reclassified from Accumulated Other Comprehensive Income (Loss) |  |
|  | Three Months Ended March 31, |  | Affected line Item in the Consolidated
|  | 2020 |  | 2019 |  | Statement of Income
|  | (in thousands) |  |
Unrealized gains and l osses on available for sale debt securities |  | $ | 249 |  |  | $ | (1,847 | ) |  | Investment securities gains, net
|  | 249 |  |  | (1,847 | ) |  | Total before tax
|  | (58 | ) |  | 430 |  |  | Income tax provision
|  | $ | 191 |  |  | $ | (1,417 | ) |  | Net of tax
Amortization of pension plan liability actuarial losses |  | $ | (104 | ) |  | $ | (80 | ) |  | Compensation and employee benefits
|  | (104 | ) |  | (80 | ) |  | Total before tax
|  | 24 |  |  | 19 |  |  | Income tax provision
|  | $ | (80 | ) |  | $ | (61 | ) |  | Net of tax
Unrealized gains from hedging instruments |  | $ | 940 |  |  | $ | — |  |  | Loans
|  | 940 |  |  | — |  |  | Total before tax
|  | (218 | ) |  | — |  |  | Income tax provision
|  | $ | 722 |  |  | $ | — |  |  | 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669686-108580 + Details
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