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Loans and Allowance for Credit Losses - Schedule of Information Regarding Credit Exposure (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		$ 162	$ 189
Total loans held for investment (Note 3)		1,503,950	1,410,653
Total nonaccrual loans		1,765	1,723	$ 1,670
Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		6,290	5,015
Financing Receivable, Prior year		1,794	4,088
Financing Receivable, Two year prior		3,359	3,078
Financing Receivable, Three year prior		2,924	1,788
Financing Receivable, Four year prior		1,573	7,204
Prior		19,363	18,530
Term Loans Total		35,303	39,703
Revolving Loans		13,844	9,507
Total loans held for investment (Note 3)		49,147	49,210
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	0	0
Current year-to-date gross write-offs, Two year prior	[1]	0	0
Current year-to-date gross write-offs, Three year prior	[1]	0	0
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	0	0
Current year-to-date gross write-offs, Term Loans Total	[1]	0	0
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	0	0
Agricultural [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		6,290	5,015
Financing Receivable, Prior year		1,794	4,088
Financing Receivable, Two year prior		3,359	3,078
Financing Receivable, Three year prior		2,924	1,788
Financing Receivable, Four year prior		1,573	7,028
Prior		19,181	18,476
Term Loans Total		35,121	39,473
Revolving Loans		13,844	9,507
Total loans held for investment (Note 3)		48,965	48,980
Agricultural [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	176
Prior		182	54
Term Loans Total		182	230
Revolving Loans		0	0
Total loans held for investment (Note 3)		182	230
Agricultural [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Agricultural [Member] | Doubtful [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Agricultural [Member] | Loss [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		33,953	23,600
Financing Receivable, Prior year		20,139	45,489
Financing Receivable, Two year prior		33,467	23,490
Financing Receivable, Three year prior		17,125	10,537
Financing Receivable, Four year prior		7,975	9,287
Prior		12,044	11,950
Term Loans Total		124,703	124,353
Revolving Loans		104,529	105,562
Total loans held for investment (Note 3)		229,232	229,915
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	0	55
Current year-to-date gross write-offs, Two year prior	[1]	0	30
Current year-to-date gross write-offs, Three year prior	[1]	0	71
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	1	2
Current year-to-date gross write-offs, Term Loans Total	[1]	1	158
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	1	158
Total nonaccrual loans		0	1	103
Commercial and Industrial [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		33,953	23,600
Financing Receivable, Prior year		20,139	45,489
Financing Receivable, Two year prior		33,374	23,462
Financing Receivable, Three year prior		17,065	10,502
Financing Receivable, Four year prior		7,948	9,214
Prior		11,816	11,882
Term Loans Total		124,295	124,149
Revolving Loans		104,519	105,559
Total loans held for investment (Note 3)		228,814	229,708
Commercial and Industrial [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		93	28
Financing Receivable, Three year prior		60	35
Financing Receivable, Four year prior		27	73
Prior		226	64
Term Loans Total		406	200
Revolving Loans		10	3
Total loans held for investment (Note 3)		416	203
Commercial and Industrial [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		2	4
Term Loans Total		2	4
Revolving Loans		0	0
Total loans held for investment (Note 3)		2	4
Commercial and Industrial [Member] | Doubtful [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Commercial and Industrial [Member] | Loss [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Construction Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	2,507
Financing Receivable, Prior year		986	2,719
Financing Receivable, Two year prior		0	552
Financing Receivable, Three year prior		530	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		1,516	5,778
Revolving Loans		13,039	15,158
Total loans held for investment (Note 3)		14,555	20,936
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	0	0
Current year-to-date gross write-offs, Two year prior	[1]	0	0
Current year-to-date gross write-offs, Three year prior	[1]	0	0
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	0	0
Current year-to-date gross write-offs, Term Loans Total	[1]	0	0
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	0
Construction Real Estate [Member] | Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	2,507
Financing Receivable, Prior year		986	2,719
Financing Receivable, Two year prior		0	552
Financing Receivable, Three year prior		530	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		1,516	5,778
Revolving Loans		12,810	15,158
Total loans held for investment (Note 3)		14,326	20,936
Construction Real Estate [Member] | Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0
Revolving Loans		0
Total loans held for investment (Note 3)		0
Construction Real Estate [Member] | Nonaccrual Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		5,439	9,775
Financing Receivable, Prior year		7,354	13,876
Financing Receivable, Two year prior		9,109	6,771
Financing Receivable, Three year prior		4,822	2,849
Financing Receivable, Four year prior		1,848	1,260
Prior		1,473	1,202
Term Loans Total		30,045	35,733
Revolving Loans		648	808
Total loans held for investment (Note 3)		30,693	36,541
Current year-to-date gross write-offs, Current year	[1]	0	8
Current year-to-date gross write-offs, Prior year	[1]	31	24
Current year-to-date gross write-offs, Two year prior	[1]	110	11
Current year-to-date gross write-offs, Three year prior	[1]	1	28
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	2	1
Current year-to-date gross write-offs, Term Loans Total	[1]	144	72
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	144	72
Total nonaccrual loans		2
Consumer Portfolio Segment [Member] | Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		5,439	9,775
Financing Receivable, Prior year		7,354	13,876
Financing Receivable, Two year prior		9,107	6,771
Financing Receivable, Three year prior		4,822	2,849
Financing Receivable, Four year prior		1,848	1,260
Prior		1,473	1,202
Term Loans Total		30,043	35,733
Revolving Loans		648	808
Total loans held for investment (Note 3)		30,691	36,541
Consumer Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Consumer Portfolio Segment [Member] | Nonaccrual Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		2	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		2	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		2	0
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		107,946	149,181
Financing Receivable, Prior year		140,667	134,289
Financing Receivable, Two year prior		112,938	107,033
Financing Receivable, Three year prior		101,041	71,754
Financing Receivable, Four year prior		68,276	43,846
Prior		163,097	137,698
Term Loans Total		693,965	643,801
Revolving Loans		168,808	143,120
Total loans held for investment (Note 3)		862,773	786,921
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	0	0
Current year-to-date gross write-offs, Two year prior	[1]	0	0
Current year-to-date gross write-offs, Three year prior	[1]	0	0
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	0	0
Current year-to-date gross write-offs, Term Loans Total	[1]	0	0
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	0	0
Commercial Real Estate Portfolio Segment [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		107,946	149,181
Financing Receivable, Prior year		140,667	134,289
Financing Receivable, Two year prior		112,938	107,033
Financing Receivable, Three year prior		101,041	71,754
Financing Receivable, Four year prior		68,276	43,846
Prior		162,743	136,361
Term Loans Total		693,611	642,464
Revolving Loans		168,808	143,120
Total loans held for investment (Note 3)		862,419	785,584
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		354	1,337
Term Loans Total		354	1,337
Revolving Loans		0	0
Total loans held for investment (Note 3)		354	1,337
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Commercial Real Estate Portfolio Segment [Member] | Loss [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		30,342	54,231
Financing Receivable, Prior year		46,871	65,148
Financing Receivable, Two year prior		58,391	29,127
Financing Receivable, Three year prior		26,702	16,391
Financing Receivable, Four year prior		14,684	12,556
Prior		46,650	40,756
Term Loans Total		223,640	218,209
Revolving Loans		55,418	49,521
Total loans held for investment (Note 3)		279,058	267,730
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	23	26
Current year-to-date gross write-offs, Two year prior	[1]	0	0
Current year-to-date gross write-offs, Three year prior	[1]	0	0
Current year-to-date gross write-offs, Four year prior	[1]	0	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	0	1
Current year-to-date gross write-offs, Term Loans Total	[1]	23	27
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	23	27
Total nonaccrual loans		1,763	1,722	$ 1,567
Residential Portfolio Segment [Member] | Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		30,342	54,231
Financing Receivable, Prior year		46,667	64,768
Financing Receivable, Two year prior		57,249	28,301
Financing Receivable, Three year prior		26,151	16,391
Financing Receivable, Four year prior		14,684	12,556
Prior		46,458	40,270
Term Loans Total		221,551	216,517
Revolving Loans		55,383	49,491
Total loans held for investment (Note 3)		276,934	266,008
Residential Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Residential Portfolio Segment [Member] | Nonaccrual Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		204	380
Financing Receivable, Two year prior		1,142	826
Financing Receivable, Three year prior		551	0
Financing Receivable, Four year prior		0	0
Prior		192	486
Term Loans Total		2,089	1,692
Revolving Loans		35	30
Total loans held for investment (Note 3)		2,124	1,722
Loans to other financial institutions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		38,492	19,400
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		38,492	19,400
Revolving Loans		0	0
Total loans held for investment (Note 3)		38,492	19,400
Current year-to-date gross write-offs, Current year	[1]	0	0
Current year-to-date gross write-offs, Prior year	[1]	0	0
Current year-to-date gross write-offs, Two year prior	[1]	0	0
Current year-to-date gross write-offs, Three year prior	[1]	0	0
Current year-to-date gross write-offs, Four year prior	[1]	0
Financing Receivable Originated Writeoffs Five or More Years Before Latest Fiscal Year, Total	[1]	0	0
Current year-to-date gross write-offs, Term Loans Total	[1]	0	0
Current year-to-date gross write-offs, Revolving Loans	[1]	0	0
Current year-to-date gross write-offs, Grand Total	[1]	0	0
Loans to other financial institutions [Member] | Performing Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		38,492	19,400
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		38,492	19,400
Revolving Loans		0	0
Total loans held for investment (Note 3)		38,492	19,400
Loans to other financial institutions [Member] | Nonperforming Financial Instruments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		0	0
Total loans held for investment (Note 3)		0	0
Loans to other financial institutions [Member] | Nonaccrual Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		0	0
Financing Receivable, Prior year		0	0
Financing Receivable, Two year prior		0	0
Financing Receivable, Three year prior		0	0
Financing Receivable, Four year prior		0	0
Prior		0	0
Term Loans Total		0	0
Revolving Loans		229	0
Total loans held for investment (Note 3)		229	0
Business Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year			177,796
Financing Receivable, Prior year			183,866
Financing Receivable, Two year prior			133,601
Financing Receivable, Three year prior			84,079
Financing Receivable, Four year prior			60,337
Prior			168,178
Term Loans Total			807,857
Revolving Loans			258,189
Total loans held for investment (Note 3)			1,066,046
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		148,189
Financing Receivable, Prior year		162,600
Financing Receivable, Two year prior		149,764
Financing Receivable, Three year prior		121,090
Financing Receivable, Four year prior		77,824
Prior		194,504
Term Loans Total		853,971
Revolving Loans		287,181
Total loans held for investment (Note 3)		1,141,152
Retail Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year		74,273
Financing Receivable, Prior year		55,211
Financing Receivable, Two year prior		67,500
Financing Receivable, Three year prior		32,054
Financing Receivable, Four year prior		16,532
Prior		48,123
Term Loans Total		293,693
Revolving Loans		69,105
Total loans held for investment (Note 3)		$ 362,798
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Current year			85,913
Financing Receivable, Prior year			81,743
Financing Receivable, Two year prior			36,450
Financing Receivable, Three year prior			19,240
Financing Receivable, Four year prior			13,816
Prior			41,958
Term Loans Total			279,120
Revolving Loans			65,487
Total loans held for investment (Note 3)			$ 344,607
[1] It is noted that write-offs in the tables above do not include checking account write-offs. Checking account write-offs during the first nine months of 2024 were $473,000 or an annualized $631,000 compared to $480,000 during the full year 2023 and $377,000 or an annualized $503,000 during the first nine months of 2023.

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