TAX EFFECT ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Statement of Income and Comprehensive Income
Adjustment of pension and postretirement benefit plans	$ 0	$ (761)
Amortization of net losses of pension and postretirement benefit plans	(1,805)	(1,467)
Unrealized holding gains (losses) on debt securities arising during the period	(21,566)	143,193
Amortization of unrealized losses of debt securities transfer from available-for-sale to held-to-maturity	(8,407)	0
Unrealized net (losses) gains on cash flow hedges	11	(749)
Reclassification adjustment for net gains included in net income	15	366
Income tax (expense) benefit	$ (31,752)	$ 140,582

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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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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