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Reclassification Adjustments Out of Other Comprehensive Income (Loss) (Tables) | 12 Months Ended
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Dec. 31, 2020
Reclassification Adjustments Out of Other Comprehensive Income (Loss) [Abstract] |
Reclassification Adjustments out of AOCI | The following table summarizes the reclassification adjustments out of AOCI:
Detail About AOCI Components |  | Amount Reclassified From AOCI |  | Affected Line Item in the Consolidated Statements of Comprehensive Income (Loss)
(In thousands) |  | Years Ended December 31, |  |
| 2020 |  |  | 2019 |  |  | 2018 |
AFS securities: |  |  |  |  |  |  |  |  |  |
(Gains) losses on AFS securities |  | $ | (3 | ) |  | $ | 79 |  |  | $ | 6,622 |  | Net securities (gains) losses
Amortization of unrealized gains related to securities transfer |  |  | 644 |  |  |  | 737 |  |  |  | 688 |  | Interest income
Tax effect |  | $ | (160 | ) |  | $ | (204 | ) |  | $ | (1,827 | ) | Income tax (benefit)
Net of tax |  | $ | 481 |  |  | $ | 612 |  |  | $ | 5,483 |  |
Cash flow hedges: |  |  |  |  |  |  |  |  |  |  |  |  |
Net unrealized losses (gains) on cash flow hedges reclassified to interest expense |  | $ | 296 |  |  | $ | (2,012 | ) |  | $ | (2,300 | ) | Interest expense
Tax effect |  | $ | (74 | ) |  | $ | 503 |  |  | $ | 575 |  | Income tax (benefit) expense
Net of tax |  | $ | 222 |  |  | $ | (1,509 | ) |  | $ | (1,725 | ) |
Pension and other benefits: |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization of net losses |  | $ | 1,535 |  |  | $ | 2,593 |  |  | $ | 1,054 |  | Other noninterest expense
Amortization of prior service costs |  |  | 92 |  |  |  | 93 |  |  |  | 91 |  | Other noninterest expense
Tax effect |  | $ | (407 | ) |  | $ | (672 | ) |  | $ | (286 | ) | Income tax (benefit)
Net of tax |  | $ | 1,220 |  |  | $ | 2,014 |  |  | $ | 859 |  |
Total reclassifications, net of tax |  | $ | 1,923 |  |  | $ | 1,117 |  |  | $ | 4,617 |  |

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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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