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, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Securities held-to-maturity, amortized cost, due in one year or less	$ 10,036
Securities held-to-maturity, fair value, due in one year or less	9,989
Securities held-to-maturity, amortized cost, due after ten years	67,313
Securities held-to-maturity, fair value, due after ten years	61,839
Securities held-to-maturity, amortized cost	75,203
Securities held-to-maturity, allowance for credit losses	(986)	$ (862)	$ (915)	$ (907)
Securities held-to-maturity, amortized cost	74,217	57,868
Securities held-to-maturity, fair value	69,719	62,029
Securities available for sale, amortized cost, due after one years through five years	79,395
Securities available for sale, fair value, due after one years through five years	78,619
Securities available for sale, amortized cost, due after five years through ten years	168,590
Securities available for sale, fair value, due after five years through ten years	162,353
Securities available for sale, amortized cost, due after ten years	23,200
Securities available for sale, fair value, due after ten years	23,143
Securities available for sale, amortized cost, total other securities	883,377	786,425
Securities available for sale, fair value, total other securities	839,869	777,236
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	67,313	50,836
Securities held-to-maturity, fair value	61,839	53,362
Total Other Securities [Member]
Securities held-to-maturity, amortized cost	67,313
Securities held-to-maturity, fair value	61,839
Securities available for sale, amortized cost, total other securities	281,221
Securities available for sale, fair value, total other securities	274,104
Collateralized Mortgage Backed Securities [Member]
Securities held-to-maturity, amortized cost	7,890	7,894
Securities held-to-maturity, amortized cost	7,890	7,894
Securities held-to-maturity, fair value	7,880	8,667
Securities available for sale, amortized cost, total other securities	590,219	578,057
Securities available for sale, fair value, total other securities	553,828	572,184
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	11,937	12,485
Securities available for sale, fair value, total other securities	$ 11,937	$ 12,485