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Investment Securities - Amortized Cost and Fair Value - Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Securities Held-to-Maturity
Amortized cost, held to maturity	$ 91,172	$ 92,009
Gross unrealized (losses)	(13,716)	(15,739)
Securities held-to-maturity, fair value	77,456	76,270
U.S. Treasuries
Securities Held-to-Maturity
Amortized cost, held to maturity	6,002	6,001
Gross unrealized (losses)	(480)	(583)
Securities held-to-maturity, fair value	5,522	5,418
U.S. government and federal agencies
Securities Held-to-Maturity
Amortized cost, held to maturity	35,341	35,349
Gross unrealized (losses)	(4,003)	(4,743)
Securities held-to-maturity, fair value	31,338	30,606
U.S. agency collateralized mortgage obligations
Securities Held-to-Maturity
Amortized cost, held to maturity	17,430	17,805
Gross unrealized (losses)	(3,594)	(3,948)
Securities held-to-maturity, fair value	13,836	13,857
Taxable municipal
Securities Held-to-Maturity
Amortized cost, held to maturity	6,037	6,041
Gross unrealized (losses)	(947)	(1,089)
Securities held-to-maturity, fair value	5,090	4,952
U.S. agency mortgage-backed
Securities Held-to-Maturity
Amortized cost, held to maturity	26,362	26,813
Gross unrealized (losses)	(4,692)	(5,376)
Securities held-to-maturity, fair value	$ 21,670	$ 21,437

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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
-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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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