Loan And Allowance For Credit Losses - Changes in Allowance for Loan Losses (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	$ 66,534,000	$ 52,499,000
Impact of adopting ASC 326		(619,000)
Initial allowance on acquired TB&T PCD loans		1,678,000
Provision for loan losses	(2,089,000)	16,048,000
Recoveries	4,528,000	2,242,000
Charge-offs	(5,508,000)	(5,314,000)
Ending balance	63,465,000	66,534,000
Commercial [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	13,609,000
Ending balance		13,609,000
Agricultural [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	1,255,000	1,206,000
Impact of adopting ASC 326		(8,000)
Provision for loan losses	2,989,000	398,000
Recoveries	36,000	31,000
Charge-offs	2,683,000	372,000
Ending balance	1,597,000	1,255,000
C&I [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	13,609,000	11,010,000
Impact of adopting ASC 326		(155,000)
Provision for loan losses	(1,879,000)	3,955,000
Recoveries	2,150,000	1,315,000
Charge-offs	(1,600,000)	(2,516,000)
Ending balance	12,280,000	13,609,000
Muncipal [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	1,552,000	1,112,000
Impact of adopting ASC 326		(16,000)
Provision for loan losses	(1,204,000)	456,000
Ending balance	348,000	1,552,000
Construction & Development [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	13,512,000	6,045,000
Impact of adopting ASC 326		(75,000)
Provision for loan losses	4,114,000	7,542,000
Recoveries	1,000
Ending balance	17,627,000	13,512,000
Farm [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	1,876,000	663,000
Impact of adopting ASC 326		(8,000)
Initial allowance on acquired TB&T PCD loans		727,000
Provision for loan losses	(1,323,000)	337,000
Recoveries	110,000	157,000
Ending balance	663,000	1,876,000
Non - Owner Occupied CRE [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	8,391,000	7,341,000
Impact of adopting ASC 326		(91,000)
Provision for loan losses	1,635,000	1,573,000
Recoveries	702,000	131,000
Charge-offs	(6,000)	(563,000)
Ending balance	10,722,000	8,391,000
Owner Occupied CRE [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	12,347,000	9,533,000
Impact of adopting ASC 326		(118,000)
Initial allowance on acquired TB&T PCD loans		847,000
Provision for loan losses	(2,109,000)	2,635,000
Recoveries	821,000	17,000
Charge-offs	(231,000)	(567,000)
Ending balance	10,828,000	12,347,000
Residential [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	12,601,000	10,392,000
Impact of adopting ASC 326		(129,000)
Initial allowance on acquired TB&T PCD loans		104,000
Provision for loan losses	(4,471,000)	2,456,000
Recoveries	96,000	151,000
Charge-offs	(93,000)	(373,000)
Ending balance	8,133,000	12,601,000
Auto [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	1,020,000	3,900,000
Impact of adopting ASC 326		(14,000)
Provision for loan losses	85,000	(2,587,000)
Recoveries	401,000	269,000
Charge-offs	(610,000)	(548,000)
Ending balance	896,000	1,020,000
Non - Auto [Member]
Loans And Leases Receivable Disclosure [Line Items]
Beginning balance	371,000	1,297,000
Impact of adopting ASC 326		(5,000)
Provision for loan losses	74,000	(717,000)
Recoveries	211,000	171,000
Charge-offs	(285,000)	(375,000)
Ending balance	$ 371,000	$ 371,000