TAX EFFECT ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Income and Comprehensive Income
Adjustment of pension and postretirement benefit plans	$ (8,644)	$ (2,929)	$ (13,856)
Amortization of net losses	(7,219)	(5,867)	(7,781)
Unrealized net holding gains (losses) on debt securities arising during the period	80,854	278,324	62,468
Reclassification adjustment for gains included in net income	0	0	5
Amortization of unrealized losses of debt securities transfer from available-for-sale to held-to-maturity	(34,577)	(8,328)	0
Unrealized net gains (losses) on cash flow hedges	11	(612)	(172)
Reclassification adjustment for net (gains) losses included in net income	15	546	(263)
Income tax benefit	$ 30,440	$ 261,134	$ 40,401

Amount of tax expense (benefit) on adjustment from accumulated other comprehensive income (loss) for amortization of gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from transfer to investment in debt security measured at amortized cost (held-to-maturity).

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-Topic 320
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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Tax effect of plan amendments that occurred that has not been recognized in net periodic benefit cost.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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