Loans and Allowance for Credit Losses - Allowance for Credit Losses Based on Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 59,075	$ 54,597	$ 54,655	$ 41,910	$ 41,910
Initial allowance on loans purchased with credit deterioration			863	2,074
Provision for credit loss expense	142	1,103	4,001	12,679	15,151
Loans charged off	833	2,076	2,178	3,493	5,634
Recoveries collected	393	359	1,436	813	1,154
Allowance for credit losses, Ending Balance	58,777	53,983	58,777	53,983	54,655
Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				2,074	2,074
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,042	1,795	1,743	1,666	1,666
Initial allowance on loans purchased with credit deterioration			272	261
Provision for credit loss expense	1	314	30	205	21
Loans charged off	0	0	2	23	205
Recoveries collected	100	0	100	0	0
Allowance for credit losses, Ending Balance	2,143	2,109	2,143	2,109	1,743
Construction and Land Development \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				261	261
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,112	1,665	1,257	1,084	1,084
Initial allowance on loans purchased with credit deterioration			0	44
Provision for credit loss expense	(674)	(408)	181	129	129
Loans charged off	0	0	0	0	0
Recoveries collected	0	0	0	0	0
Allowance for credit losses, Ending Balance	1,438	1,257	1,438	1,257	1,257
Agricultural \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				44	44
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,523	2,570	2,330	2,322	2,322
Initial allowance on loans purchased with credit deterioration			3	328
Provision for credit loss expense	269	27	1,355	117	(160)
Loans charged off	45	45	186	241	371
Recoveries collected	19	108	264	134	211
Allowance for credit losses, Ending Balance	3,766	2,660	3,766	2,660	2,330
Residential Properties \| Real Estate Loan \| 1-4 Family \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				328	328
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	28,856	25,664	26,246	19,660	19,660
Initial allowance on loans purchased with credit deterioration			478	646
Provision for credit loss expense	(796)	(52)	1,384	5,764	6,415
Loans charged off	7	55	414	535	535
Recoveries collected	8	23	367	45	60
Allowance for credit losses, Ending Balance	28,061	25,580	28,061	25,580	26,246
Commercial \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				646	646
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	886	906	983	1,526	1,526
Initial allowance on loans purchased with credit deterioration			0	0
Provision for credit loss expense	(246)	(90)	(250)	(711)	(544)
Loans charged off	0	0	93	0	0
Recoveries collected	38	0	38	1	1
Allowance for credit losses, Ending Balance	678	816	678	816	983
Agricultural Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				0	0
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	19,496	19,842	19,241	13,485	13,485
Initial allowance on loans purchased with credit deterioration			94	795
Provision for credit loss expense	1,271	342	1,343	5,950	7,940
Loans charged off	389	1,600	424	1,686	3,118
Recoveries collected	63	24	187	64	139
Allowance for credit losses, Ending Balance	20,441	18,608	20,441	18,608	19,241
Commercial and Industrial Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				795	795
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,160	2,155	2,855	2,167	2,167
Initial allowance on loans purchased with credit deterioration			16	0
Provision for credit loss expense	317	970	(42)	1,225	1,350
Loans charged off	392	376	1,059	1,008	1,405
Recoveries collected	165	204	480	569	743
Allowance for credit losses, Ending Balance	$ 2,250	$ 2,953	$ 2,250	2,953	2,855
Consumer Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance				$ 0	$ 0

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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