Consolidated Statements of Comprehensive Income - Unaudited (Parentheticals) - 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]
Unrealized investment (losses) gains, tax (benefit) expense	$ 275	$ 34	$ (1,035)	$ 1,804
Net unrealized gains (losses) on interest rate swaps, before reclassification, tax expense (benefit)	1,039	0	37	0
Net unrealized gains (loss) on interest rate swaps in cash flow hedges, tax expense	(87)	0	(126)	0
Net unrealized gains (losses) on interest rate swaps, after reclassification, tax expense (benefit)	952	0	(89)	0
Change in unfunded pension liability related to unrealized loss, prior service cost and transition obligation, tax expense	$ 8	$ 6	$ 22	$ 12

Amount, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and 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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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.

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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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Amount of tax (expense) benefit for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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