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Reclassification Adjustments Out of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Net securities (gains) losses | $ (92) | $ (4,641) | $ 2,091 | $ (9,639)
Interest income | 97,174 | 89,085 | 192,348 | 184,151
Other noninterest expense | 5,518 | 5,690 | 11,753 | 10,770
Income tax (benefit) | 9,203 | 8,658 | 18,594 | 18,244
Net income | 32,716 | 30,072 | 66,539 | 63,730
Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Total reclassifications, net of tax | 1,156 | 3,905 | 1,567 | 8,227
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Income tax (benefit) | (23) | (1,141) | (47) | (2,419)
Net income | 68 | 3,418 | 140 | 7,254
Losses on AFS Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Net securities (gains) losses | 0 | 4,450 | 0 | 9,450
Amortization of Unrealized Gains Related to Securities Transfer [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Interest income | 91 | 109 | 187 | 223
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Income tax (benefit) | (363) | (162) | (476) | (325)
Net income | 1,088 | 487 | 1,427 | 973
Amortization of Net Losses [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Other noninterest expense | 1,454 | 640 | 1,908 | 1,280
Amortization of Prior Service Costs [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] |  |  |  |
Reclassification Adjustment out of AOCI [Abstract] |  |  |  |
Other noninterest expense | $ (3) | $ 9 | $ (5) | $ 18

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