Securities - Realized Gain (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Securities
Proceeds from sales of securities	$ 26,873		$ 35,075	$ 18,006
Gross realized gains on securities	262		267	17
Gross realized losses on securities	(18)	$ (1)	(21)	(42)
Net realized gains (losses)	244	$ (1)	246	(25)
Income tax (expense) benefit on net realized gains (losses)	$ (69)		$ (70)	$ 7
Effective tax rate applied (as a percent)	28.30%	0.00%	28.50%	28.00%
Available-for-sale Securities Pledged as Collateral	$ 353,200		$ 353,200		$ 335,800

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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 cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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