Loans Held for Investment and Allowance for Credit Losses on Loans - Gross Charges-offs by Year of Orgination (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year gross charge-offs	$ 933
Fiscal year before current fiscal year gross charge-offs	1,436
Two years before current fiscal year gross charge-offs	517
Three years before current fiscal year gross charge-offs	633
Four years before current fiscal year gross charge-offs	277
Prior gross charge-offs	425
Revolving Loans Amortized Cost Basis gross charge-offs	19
Total current-period gross charge-offs	4,240
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year gross charge-offs	174
Fiscal year before current fiscal year gross charge-offs	196
Two years before current fiscal year gross charge-offs	26
Three years before current fiscal year gross charge-offs	203
Four years before current fiscal year gross charge-offs	165
Prior gross charge-offs	158
Total current-period gross charge-offs	922
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Prior gross charge-offs	3
Total current-period gross charge-offs	3
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Fiscal year before current fiscal year gross charge-offs	3
Three years before current fiscal year gross charge-offs	2
Prior gross charge-offs	1
Total current-period gross charge-offs	6
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Fiscal year before current fiscal year gross charge-offs	94
Total current-period gross charge-offs	94
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Two years before current fiscal year gross charge-offs	91
Three years before current fiscal year gross charge-offs	44
Four years before current fiscal year gross charge-offs	5
Prior gross charge-offs	25
Total current-period gross charge-offs	165
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Fiscal year before current fiscal year gross charge-offs	4
Two years before current fiscal year gross charge-offs	19
Four years before current fiscal year gross charge-offs	1
Prior gross charge-offs	36
Total current-period gross charge-offs	60
Real Estate [Member] | Agriculture Member
Financing Receivable, Credit Quality Indicator [Line Items]
Fiscal year before current fiscal year gross charge-offs	154
Two years before current fiscal year gross charge-offs	9
Three years before current fiscal year gross charge-offs	317
Four years before current fiscal year gross charge-offs	14
Prior gross charge-offs	2
Total current-period gross charge-offs	496
Commercial Non-real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year gross charge-offs	390
Fiscal year before current fiscal year gross charge-offs	351
Two years before current fiscal year gross charge-offs	111
Three years before current fiscal year gross charge-offs	22
Four years before current fiscal year gross charge-offs	51
Prior gross charge-offs	160
Total current-period gross charge-offs	1,085
Consumer Non-real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year gross charge-offs	312
Fiscal year before current fiscal year gross charge-offs	632
Two years before current fiscal year gross charge-offs	261
Three years before current fiscal year gross charge-offs	45
Four years before current fiscal year gross charge-offs	41
Prior gross charge-offs	40
Revolving Loans Amortized Cost Basis gross charge-offs	19
Total current-period gross charge-offs	1,350
Oil and Gas [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year gross charge-offs	57
Fiscal year before current fiscal year gross charge-offs	2
Total current-period gross charge-offs	$ 59