TAX EFFECT ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Income and Comprehensive Income
Adjustment of pension and postretirement benefit plans	$ (13,856)	$ 3,387	$ 8,203
Amortization of net losses	(7,781)	(8,042)	(8,817)
Unrealized holding (losses) gains on debt securities arising during the period	62,468	(51,213)	(20,113)
Reclassification adjustment for (gains) losses included in net income	5	6	(4)
Unrealized net gains (losses) on cash flow hedges	(172)	2,472	1,302
Reclassification adjustment for net losses included in net income	(263)	(2,084)	(1,496)
Income tax benefit (expense)	$ 40,401	$ (55,474)	$ (20,925)

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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-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for 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) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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

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

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