Loans and Allowance for Credit Losses - Allowance for Credit Losses Based on Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 58,474	$ 55,418	$ 54,655	$ 41,910	$ 41,910
Initial allowance on loans purchased with credit deterioration			863	2,074
Provision for credit loss expense	907	(560)	3,859	11,576	15,151
Loans charged off	571	449	1,345	1,417	5,634
Recoveries collected	265	188	1,043	454	1,154
Allowance for credit losses, Ending Balance	59,075	54,597	59,075	54,597	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	1,988	2,286	1,743	1,666	1,666
Initial allowance on loans purchased with credit deterioration			272	261
Provision for credit loss expense	54	(468)	29	(109)	21
Loans charged off	0	23	2	23	205
Recoveries collected	0	0	0	0	0
Allowance for credit losses, Ending Balance	2,042	1,795	2,042	1,795	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	1,971	1,628	1,257	1,084	1,084
Initial allowance on loans purchased with credit deterioration			0	44
Provision for credit loss expense	141	37	855	535	129
Loans charged off	0	0	0	0	0
Recoveries collected	0	0	0	2	0
Allowance for credit losses, Ending Balance	2,112	1,665	2,112	1,665	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	3,728	3,093	2,330	2,322	2,322
Initial allowance on loans purchased with credit deterioration			3	328
Provision for credit loss expense	(178)	(527)	1,086	90	(160)
Loans charged off	69	14	141	196	371
Recoveries collected	42	18	245	26	211
Allowance for credit losses, Ending Balance	3,523	2,570	3,523	2,570	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	30,345	25,737	26,246	19,660	19,660
Initial allowance on loans purchased with credit deterioration			478	646
Provision for credit loss expense	(1,433)	(86)	2,180	5,816	6,415
Loans charged off	68	0	407	480	535
Recoveries collected	12	13	359	22	60
Allowance for credit losses, Ending Balance	28,856	25,664	28,856	25,664	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	1,051	881	983	1,526	1,526
Initial allowance on loans purchased with credit deterioration			0	0
Provision for credit loss expense	(72)	24	(4)	(621)	(544)
Loans charged off	93	0	93	0	0
Recoveries collected	0	1	0	1	1
Allowance for credit losses, Ending Balance	886	906	886	906	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	17,348	18,954	19,241	13,485	13,485
Initial allowance on loans purchased with credit deterioration			94	795
Provision for credit loss expense	2,117	934	72	5,608	7,940
Loans charged off	32	68	35	86	3,118
Recoveries collected	63	22	124	40	139
Allowance for credit losses, Ending Balance	19,496	19,842	19,496	19,842	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	2,043	2,839	2,855	2,167	2,167
Initial allowance on loans purchased with credit deterioration			16	0
Provision for credit loss expense	278	(474)	(359)	257	1,350
Loans charged off	309	344	667	632	1,405
Recoveries collected	148	134	315	363	743
Allowance for credit losses, Ending Balance	$ 2,160	$ 2,155	$ 2,160	2,155	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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