TAX EFFECT ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Income and Comprehensive Income
Adjustment of pension and postretirement benefit plans	$ (8,495)	$ (8,644)	$ (2,929)
Amortization of net losses	(5,427)	(7,219)	(5,867)
Unrealized net holding gains (losses) on debt securities arising during the period	(27,165)	80,854	278,324
Reclassification adjustment for gains included in net income	0	0	0
Amortization of unrealized losses of debt securities transfer from available-for-sale to held-to-maturity	(35,913)	(34,577)	(8,328)
Unrealized net gains (losses) on cash flow hedges	0	11	(612)
Reclassification adjustment for net (gains) losses included in net income	0	15	546
Income tax (expense) benefit	$ (77,000)	$ 30,440	$ 261,134

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).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481889/320-10-35-10B

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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