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Investment securities (Tables)

12 Months Ended

Dec. 31, 2025

Investments, Debt and Equity Securities [Abstract]

Unrealized Gain (Loss) on Investments [Table Text Block]

The following tables show the amortized cost, gross unrealized gains and losses and fair value of securities available for sale, by security type as of December 31, 2025 and 2024. 

			2025
			Amortized Cost						Gross Unrealized Gains						Gross Unrealized Losses						Fair Value
Securities available for sale:
State and political subdivisions			$	198,083					$	1					$	(34,820)					$	163,264
Collateralized mortgage obligations (1)			234,217						—						(40,534)						193,683
Mortgage-backed securities (1)			113,358						—						(17,216)						96,142
Collateralized loan obligations			2,307						1						(1)						2,307
Corporate notes			13,750						—						(699)						13,051
			$	561,715					$	2					$	(93,270)					$	468,447

			2024
			Amortized Cost						Gross Unrealized Gains						Gross Unrealized Losses						Fair Value
Securities available for sale:
State and political subdivisions			$	215,942					$	—					$	(41,797)					$	174,145
Collateralized mortgage obligations (1)			278,754						—						(59,490)						219,264
Mortgage-backed securities (1)			145,992						—						(26,173)						119,819
Collateralized loan obligations			18,932						33						—						18,965
Corporate notes			13,750						—						(1,378)						12,372
			$	673,370					$	33					$	(128,838)					$	544,565

(1)Collateralized mortgage obligations and mortgage-backed securities consist of residential and commercial mortgage pass-through securities and collateralized mortgage obligations guaranteed by FNMA, FHLMC, GNMA and SBA.

Investments Classified by Contractual Maturity Date [Table Text Block]

The amortized cost and fair value of securities available for sale as of December 31, 2025, by contractual maturity, are shown below. Certain securities have call features that allow the issuer to call the securities prior to maturity. Expected maturities may differ from contractual maturities for collateralized mortgage obligations and mortgage-backed securities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Therefore, collateralized mortgage obligations and mortgage-backed securities are not included in the maturity categories within the following maturity summary.

			2025
			Amortized Cost						Fair Value
Due after five years through ten years			$	30,902					$	28,227
Due after ten years			183,238						150,395
			214,140						178,622
Collateralized mortgage obligations and mortgage-backed securities			347,575						289,825
			$	561,715					$	468,447

Schedule of Realized Gain (Loss) [Table Text Block]

The details of the sales of securities available for sale for the years ended December 31, 2025, 2024 and 2023 are summarized in the following table.

			2025						2024						2023
Proceeds from sales			$	63,690					$	11,841					$	11,285
Gross gains on sales			3						—						—
Gross losses on sales			3,962						1,172						431

Schedule of Unrealized Loss on Investments [Table Text Block]

The following tables show the fair value and gross unrealized losses, aggregated by investment type and length of time that individual securities have been in a continuous loss position, as of December 31, 2025 and 2024.  

						2025
						Less than 12 months																		12 months or longer																		Total
						Fair Value						Gross Unrealized Losses						No. of Securities						Fair Value						Gross Unrealized Losses						No. of Securities						Fair Value						Gross Unrealized Losses
Securities available for sale:
State and political subdivisions						$	—					$	—					—						$	163,173					$	(34,820)					68						$	163,173					$	(34,820)
Collateralized mortgage obligations						—						—						—						193,683						(40,534)						53						193,683						(40,534)
Mortgage-backed securities						—						—						—						96,142						(17,216)						22						96,142						(17,216)
Collateralized loan obligations						1,110						(1)						1						—						—						—						1,110						(1)
Corporate notes						—						—						—						13,052						(699)						8						13,052						(699)
						$	1,110					$	(1)					1						$	466,050					$	(93,269)					151						$	467,160					$	(93,270)

						2024
						Less than 12 months																		12 months or longer																		Total
						Fair Value						Gross Unrealized Losses						No. of Securities						Fair Value						Gross Unrealized Losses						No. of Securities						Fair Value						Gross Unrealized Losses
Securities available for sale:
State and political subdivisions						$	4,485					$	(271)					7						$	169,650					$	(41,526)					90						$	174,135					$	(41,797)
Collateralized mortgage obligations						—						—						—						219,264						(59,490)						69						219,264						(59,490)
Mortgage-backed securities						610						(3)						1						119,209						(26,170)						25						119,819						(26,173)
Corporate notes						—						—						—						12,372						(1,378)						8						12,372						(1,378)
						$	5,095					$	(274)					8						$	520,495					$	(128,564)					192						$	525,590					$	(128,838)

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Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments.

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Tabular disclosure of the proceeds from sales of available-for-sale securities and the gross realized gains and gross realized losses that have been included in earnings as a result of those sales.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

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