Investment Securities - Cost basis and fair values of investment securities (Details) - USD ($)	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Information concerning investments with unrealized gains and losses
Investment securities available for sale, Cost Basis	$ 179,385,000	$ 172,857,000
Investment securities available for sale, Gross Unrealized Gains	414,000	186,000
Investment securities available for sale, Gross Unrealized Losses	(14,604,000)	(17,063,000)
Investment securities available for sale, Allowance for credit losses	(1,000,000)	(360,000)	$ (116,000)	$ (926,000)
Available for sale, Fair Value	164,195,000	155,620,000
Investment securities - HTM, Carrying Value	67,259,000	63,837,000
Investment securities held to maturity, Gross Unrealized Gains	44,000	28,000
Investment securities held to maturity, Gross Unrealized Losses	(4,647,000)	(5,394,000)
Investment securities - HTM, Fair Value	62,656,000	58,471,000
U.S. Agency
Information concerning investments with unrealized gains and losses
Investment securities available for sale, Cost Basis	5,317,000	5,345,000
Investment securities available for sale, Gross Unrealized Losses	(564,000)	(679,000)
Available for sale, Fair Value	4,753,000	4,666,000
Investment securities - HTM, Carrying Value	2,500,000	2,500,000
Investment securities held to maturity, Gross Unrealized Losses	(310,000)	(365,000)
Investment securities - HTM, Fair Value	2,190,000	2,135,000
U.S. Agency mortgage-backed securities
Information concerning investments with unrealized gains and losses
Investment securities available for sale, Cost Basis	111,450,000	104,227,000
Investment securities available for sale, Gross Unrealized Gains	256,000	90,000
Investment securities available for sale, Gross Unrealized Losses	(11,268,000)	(12,783,000)
Available for sale, Fair Value	100,438,000	91,534,000
Investment securities - HTM, Carrying Value	30,404,000	26,966,000
Investment securities held to maturity, Gross Unrealized Gains	44,000	28,000
Investment securities held to maturity, Gross Unrealized Losses	(2,091,000)	(2,403,000)
Investment securities - HTM, Fair Value	28,357,000	24,591,000
Municipal
Information concerning investments with unrealized gains and losses
Investment securities available for sale, Cost Basis	8,460,000	9,031,000
Investment securities available for sale, Gross Unrealized Gains	2,000	2,000
Investment securities available for sale, Gross Unrealized Losses	(551,000)	(670,000)
Available for sale, Fair Value	7,911,000	8,363,000
Investment securities - HTM, Carrying Value	30,952,000	30,959,000
Investment securities held to maturity, Gross Unrealized Losses	(2,072,000)	(2,553,000)
Investment securities - HTM, Fair Value	28,880,000	28,406,000
Corporate bonds
Information concerning investments with unrealized gains and losses
Investment securities available for sale, Cost Basis	54,158,000	54,254,000
Investment securities available for sale, Gross Unrealized Gains	156,000	94,000
Investment securities available for sale, Gross Unrealized Losses	(2,221,000)	(2,931,000)
Investment securities available for sale, Allowance for credit losses	(1,000,000)	(360,000)	$ (116,000)	$ (926,000)
Available for sale, Fair Value	51,093,000	51,057,000
Corporate bonds and other securities
Information concerning investments with unrealized gains and losses
Investment securities - HTM, Carrying Value	3,403,000	3,412,000
Investment securities held to maturity, Gross Unrealized Losses	(174,000)	(73,000)
Investment securities - HTM, Fair Value	$ 3,229,000	$ 3,339,000

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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Amortized cost excluding accrued interest, before allowance for credit loss, 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 excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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