Investment Securities - Gross unrealized losses (Details) $ in Thousands	3 Months Ended
Mar. 31, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Investment securities available-for-sale
Number of Holdings \| security	128	129
Unrealized losses less than 12 months	$ (3)	$ (3)
Fair value less than 12 months	489	532
Unrealized losses over 12 months	(101,460)	(98,020)
Fair value over 12 months	471,356	485,527
Total Unrealized losses	(101,463)	(98,023)
Total Fair value	471,845	486,059
Allowance for Credit Losses	207	213
Debt security allowance for credit loss charge-offs	0
Debt security allowance for credit loss recoveries	0
Held to Maturity, Excluding Accrued Interest, Past Due	$ 0	$ 0
U. S. Treasury and agencies
Investment securities available-for-sale
Number of Holdings \| security	1	1
Unrealized losses less than 12 months	$ (3)	$ (3)
Fair value less than 12 months	454	489
Total Unrealized losses	(3)	(3)
Total Fair value	$ 454	$ 489
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Number of Holdings \| security	111	112
Fair value less than 12 months	$ 35	$ 43
Unrealized losses over 12 months	(92,516)	(88,547)
Fair value over 12 months	420,815	435,505
Total Unrealized losses	(92,516)	(88,547)
Total Fair value	$ 420,850	$ 435,548
Mortgage backed securities - Commercial
Investment securities available-for-sale
Number of Holdings \| security	1	1
Unrealized losses over 12 months	$ (120)	$ (123)
Fair value over 12 months	1,351	1,353
Total Unrealized losses	(120)	(123)
Total Fair value	$ 1,351	$ 1,353
Asset backed securities
Investment securities available-for-sale
Number of Holdings \| security	3	3
Unrealized losses over 12 months	$ (1)	$ (1)
Fair value over 12 months	22	25
Total Unrealized losses	(1)	(1)
Total Fair value	$ 22	$ 25
Corporate bonds
Investment securities available-for-sale
Number of Holdings \| security	12	12
Unrealized losses over 12 months	$ (8,823)	$ (9,349)
Fair value over 12 months	49,168	48,644
Total Unrealized losses	(8,823)	(9,349)
Total Fair value	$ 49,168	$ 48,644

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