Amount of investment in debt security measured at amortized cost, before allowance for credit losses.

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Amortized cost 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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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Securities - Securities Available-for-sale and Held-to-maturity by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Securities held-to-maturity, amortized cost, due after ten years	$ 67,128
Securities held-to-maturity, fair value, due after ten years	52,727
Securities held-to-maturity, amortized cost	75,008
Securities held-to-maturity, allowance for credit losses	(1,096)	$ (1,085)	$ (862)	$ (843)	$ (844)	$ (907)
Securities held-to-maturity, amortized cost	73,912		57,868
Securities held-to-maturity, fair value	59,713		62,029
Securities available for sale, amortized cost, due in one year or less	10,016
Securities available for sale, fair value, due in one year or less	9,907
Securities available for sale, amortized cost, due after one years through five years	134,500
Securities available for sale, fair value, due after one years through five years	127,090
Securities available for sale, amortized cost, due after five years through ten years	195,895
Securities available for sale, fair value, due after five years through ten years	181,787
Securities available for sale, amortized cost, due after ten years	22,282
Securities available for sale, fair value, due after ten years	21,580
Securities available for sale, amortized cost, total other securities	925,633		786,425
Securities available for sale, fair value, total other securities	819,861		777,236
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	67,128		50,836
Securities held-to-maturity, fair value	52,727		53,362
Total Other Securities [Member]
Securities held-to-maturity, amortized cost	67,128
Securities held-to-maturity, fair value	52,727
Securities available for sale, amortized cost, total other securities	362,693
Securities available for sale, fair value, total other securities	340,364
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,880		7,894
Securities held-to-maturity, amortized cost	7,880		7,894
Securities held-to-maturity, fair value	6,986		8,667
Securities available for sale, amortized cost, total other securities	551,809		578,057
Securities available for sale, fair value, total other securities	468,366		572,184
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	11,131		12,485
Securities available for sale, fair value, total other securities	$ 11,131		$ 12,485