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Investment Securities - Amortized Cost and Fair Value - Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Securities Held-to-Maturity
Amortized cost, held to maturity	$ 92,863	$ 95,505
Gross unrealized (losses)	(13,132)	(15,973)
Securities held-to-maturity, fair value	79,731	79,532
U.S. Treasuries
Securities Held-to-Maturity
Amortized cost, held to maturity	6,002	6,001
Gross unrealized (losses)	(501)	(667)
Securities held-to-maturity, fair value	5,501	5,334
U.S. government and federal agencies
Securities Held-to-Maturity
Amortized cost, held to maturity	35,359	35,434
Gross unrealized (losses)	(3,874)	(5,100)
Securities held-to-maturity, fair value	31,485	30,334
U.S. agency collateralized mortgage obligations
Securities Held-to-Maturity
Amortized cost, held to maturity	18,227	19,395
Gross unrealized (losses)	(3,511)	(4,095)
Securities held-to-maturity, fair value	14,716	15,300
Taxable municipal
Securities Held-to-Maturity
Amortized cost, held to maturity	6,045	6,057
Gross unrealized (losses)	(887)	(1,101)
Securities held-to-maturity, fair value	5,158	4,956
U.S. agency mortgage-backed
Securities Held-to-Maturity
Amortized cost, held to maturity	27,230	28,618
Gross unrealized (losses)	(4,359)	(5,010)
Securities held-to-maturity, fair value	$ 22,871	$ 23,608

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Fair value of investment in debt security measured at amortized cost excluding accrued interest (held-to-maturity).

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- Definition

Amount excluding accrued interest, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
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