CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net change in Unrealized (losses) gains, tax (benefit) expense	$ 7,615	$ 1,169	$ (14,361)	$ 15,707
Reclassification adjustment for gains, tax expense	0	458	79	624
Amortization of unrealized gain on securities reclassified to held-to-maturity, tax expense	9	18	14	38
Change in unfunded pension liability related to unrealized (loss) gain, prior service cost and transition obligation, tax (benefit) expense	(8)	8	(13)	(7)
Pension settlement, tax	0	67	0	67
Reclassification adjustment related to derivatives, tax benefit (expense)	0	(8)	0	493
Amortization of unrealized gain on terminated cash flow hedges, tax benefit	(35)	35	(70)	(35)
Equity method investment tax benefit	$ 0	$ 0	$ (86)	$ 0

Amount of tax expense (benefit) for increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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

+ References

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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, 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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Other Comprehensive Income Amortization Of Unrealized Gains On Securities Transferred From Available For Sale To Held To Maturity Tax

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Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost And Transition Asset Credit Tax

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Other Comprehensive Income (Loss), Cash Flow Hedge, Amortization Of Unrealized Gain (Loss), After Reclassification, Tax

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Other Comprehensive Income (Loss), Equity Method Investment, Tax

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