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	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Securities held-to-maturity, amortized cost, due after ten years	$ 66,740
Securities held-to-maturity, fair value, due after ten years	60,732
Securities held-to-maturity, amortized cost	74,610
Securities held-to-maturity, allowance for credit losses	(1,087)	$ (1,100)	$ (986)	$ (862)
Securities held-to-maturity, amortized cost	73,523	73,711
Securities held-to-maturity, fair value	67,869	62,550
Securities available for sale, amortized cost, due in one year or less	59,843
Securities available for sale, fair value, due in one year or less	58,258
Securities available for sale, amortized cost, due after one years through five years	74,798
Securities available for sale, fair value, due after one years through five years	69,629
Securities available for sale, amortized cost, due after five years through ten years	236,428
Securities available for sale, fair value, due after five years through ten years	221,597
Securities available for sale, amortized cost, due after ten years	71,892
Securities available for sale, fair value, due after ten years	70,874
Securities available for sale, amortized cost, total other securities	898,819	826,881
Securities available for sale, fair value, total other securities	811,928	735,357
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	66,740	66,936
Securities held-to-maturity, fair value	60,732	55,561
Total Other Securities [Member]
Securities held-to-maturity, amortized cost	66,740
Securities held-to-maturity, fair value	60,732
Securities available for sale, amortized cost, total other securities	442,961
Securities available for sale, fair value, total other securities	420,358
Collateralized Mortgage Backed Securities
Securities held-to-maturity, amortized cost	7,870	7,875
Securities held-to-maturity, amortized cost	7,870
Securities held-to-maturity, fair value	7,137	6,989
Securities available for sale, amortized cost, total other securities	444,398	454,320
Securities available for sale, fair value, total other securities	380,110	384,283
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	11,460	11,211
Securities available for sale, fair value, total other securities	$ 11,460	$ 11,211