Debt and Equity Securities - Amortized cost, gross unrealized gains and losses, and fair value of securities available-for-sale and equity securities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt securities:
Amortized cost	$ 37,069	$ 54,492
Gross Unrealized Gains	1	4
Gross Unrealized Losses	(2,242)	(2,449)
Fair Value	34,828	52,047
Equity Securities - Fair Value	771	762
Agency bonds
Debt securities:
Amortized cost	24,242	21,243
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1,969)	(2,126)
Fair Value	22,273	19,117
Treasury securities
Debt securities:
Amortized cost	9,801	29,859
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(11)	(42)
Fair Value	9,790	29,819
Mortgage-backed securities
Debt securities:
Amortized cost	90	97
Gross Unrealized Gains	1	2
Gross Unrealized Losses	0	0
Fair Value	91	99
Collateralized mortgage obligations
Debt securities:
Amortized cost	2,936	3,293
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(262)	(281)
Fair Value	$ 2,674	$ 3,012

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).

+ References

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Amount excluding accrued interest, 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 investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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