TAX EFFECT ALLOCATED TO EACH COMPONENT OF OTHER COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Income and Comprehensive Income
Amortization of net losses of pension and postretirement benefit plans	$ (2,204)	$ (2,101)	$ (6,611)	$ (6,301)
Amortization of prior service credit of pension and postretirement benefit plans	0	339	0	1,016
Unrealized holding gains (losses) on debt securities arising during the period	(2,583)	3,936	(24,032)	13,701
Reclassification adjustment for gains included in net income	4	0	4	0
Unrealized net (losses) gains on cash flow hedges	337	(133)	1,009	(506)
Reclassification adjustment for net losses (gains) included in net income	(501)	(58)	(1,221)	339
Income tax (expense) benefit	$ (4,955)	$ 1,983	$ (30,859)	$ 8,249

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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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 of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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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 of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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