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Investment Securities - Narrative (Details)	9 Months Ended
	Sep. 30, 2025 USD ($) security bond state company	Sep. 30, 2024 USD ($) security	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($) security	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 30, 2014 USD ($)
Debt Securities, Available-for-sale [Line Items]
AFS allowance	$ 0
HTM allowance for credit losses	186,000	$ 224,000	$ 198,000	$ 196,000	$ 149,000	$ 434,000
Amortized cost	362,738,000	377,859,000		$ 369,900,000
Gains or losses on the sale of securities	$ 0	$ 0
Number of securities temporarily impaired (security) | security	233	226		243
Financing receivable, threshold period past due	30 days
Debt securities, held-to-maturity, nonaccrual	$ 0
Amortized cost of securities transferred							$ 89,780,000
Fair value of securities transferred							89,757,000
Net unrealized loss, net of taxes on transferred securities							$ 15,000
Unamortized balance of net unrealized losses transferred	$ 40,000	$ 49,000		$ 47,000
Number of states | state	6
FHLB stock investment	$ 5,879,000	5,383,000		6,166,000
Federal reserve bank stock	1,037,000	1,037,000		1,037,000
Impairment losses	0
Other equity securities
Debt Securities, Available-for-sale [Line Items]
Securities pledged as collateral	365,383,000	344,261,000		349,833,000
Agency and mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
HTM allowance for credit losses	$ 0
Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Number of private activity bonds | bond	2
Amortized cost	$ 18,536,000
Corporate securities
Debt Securities, Available-for-sale [Line Items]
HTM allowance for credit losses	109,000	138,000	$ 119,000	116,000	$ 93,000	$ 222,000
Amortized cost	$ 26,000,000	33,750,000		27,250,000
Number of individual companies | company	14
U.S. Treasury & Agency securities
Debt Securities, Available-for-sale [Line Items]
HTM allowance for credit losses	$ 0
Amortized cost	$ 38,100,000	$ 38,100,000		$ 38,100,000

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