Loans - Impaired Loan Data (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	$ 20,129	$ 15,485
With An Allowance Recorded	7,876	9,325
Loans Including Purchased Credit Impaired Loans	28,384	24,957
Recorded investment
With No Related Allowance Recorded	19,249	14,674
With An Allowance Recorded	7,865	9,134
Loans Including Purchased Credit Impaired Loans	27,361	23,955
Related allowance
With An Allowance Recorded	1,925	3,149
Total Impaired Loans	2,010	3,155
Average Recorded Investment
With No Related Allowance Recorded	17,376	18,818
With An Allowance Recorded	7,766	5,067
Loans Including Purchased Credit Impaired Loans	25,476	24,071
Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	379	147
Recorded investment
Loans Including Purchased Credit Impaired Loans	247	147
Related allowance
With An Allowance Recorded	85	6
Purchased Credit Impaired Loans	85	6
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	334	186
Construction, land & land development
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	6,969	67
With An Allowance Recorded	0	0
Loans Including Purchased Credit Impaired Loans	7,087	132
Recorded investment
With No Related Allowance Recorded	6,982	67
With An Allowance Recorded	0	0
Loans Including Purchased Credit Impaired Loans	7,076	132
Related allowance
With An Allowance Recorded	0	0
Total Impaired Loans	0	0
Average Recorded Investment
With No Related Allowance Recorded	2,841	168
With An Allowance Recorded	0	80
Loans Including Purchased Credit Impaired Loans	2,937	328
Construction, land & land development | Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	118	65
Recorded investment
Loans Including Purchased Credit Impaired Loans	94	65
Related allowance
With An Allowance Recorded	0	0
Purchased Credit Impaired Loans	0	0
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	96	80
Other commercial real estate
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	11,978	12,455
With An Allowance Recorded	6,292	6,379
Loans Including Purchased Credit Impaired Loans	18,270	18,868
Recorded investment
With No Related Allowance Recorded	11,105	11,639
With An Allowance Recorded	6,325	6,385
Loans Including Purchased Credit Impaired Loans	17,430	18,058
Related allowance
With An Allowance Recorded	1,436	1,939
Total Impaired Loans	1,436	1,939
Average Recorded Investment
With No Related Allowance Recorded	12,190	13,924
With An Allowance Recorded	5,945	3,898
Loans Including Purchased Credit Impaired Loans	18,198	17,857
Other commercial real estate | Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	0	34
Recorded investment
Loans Including Purchased Credit Impaired Loans	0	34
Related allowance
With An Allowance Recorded	0	0
Purchased Credit Impaired Loans	0	0
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	63	35
Residential real estate
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	1,140	2,706
With An Allowance Recorded	1,274	757
Loans Including Purchased Credit Impaired Loans	2,428	3,474
Recorded investment
With No Related Allowance Recorded	1,122	2,711
With An Allowance Recorded	1,230	760
Loans Including Purchased Credit Impaired Loans	2,363	3,482
Related allowance
With An Allowance Recorded	226	137
Total Impaired Loans	230	143
Average Recorded Investment
With No Related Allowance Recorded	2,142	3,693
With An Allowance Recorded	703	367
Loans Including Purchased Credit Impaired Loans	2,858	4,084
Residential real estate | Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	14	11
Recorded investment
Loans Including Purchased Credit Impaired Loans	11	11
Related allowance
With An Allowance Recorded	4	6
Purchased Credit Impaired Loans	4	6
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	13	24
Commercial, financial, & agricultural
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	42	257
With An Allowance Recorded	310	2,189
Loans Including Purchased Credit Impaired Loans	407	2,483
Recorded investment
With No Related Allowance Recorded	40	257
With An Allowance Recorded	310	1,989
Loans Including Purchased Credit Impaired Loans	396	2,283
Related allowance
With An Allowance Recorded	263	1,073
Total Impaired Loans	263	1,073
Average Recorded Investment
With No Related Allowance Recorded	203	910
With An Allowance Recorded	1,118	722
Loans Including Purchased Credit Impaired Loans	1,370	1,679
Commercial, financial, & agricultural | Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	55	37
Recorded investment
Loans Including Purchased Credit Impaired Loans	46	37
Related allowance
With An Allowance Recorded	0	0
Purchased Credit Impaired Loans		0
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	49	47
Consumer & other
Unpaid Contractual Principal Balance
With No Related Allowance Recorded	0	0
With An Allowance Recorded	0	0
Loans Including Purchased Credit Impaired Loans	192	0
Recorded investment
With No Related Allowance Recorded	0	0
With An Allowance Recorded	0	0
Loans Including Purchased Credit Impaired Loans	96	0
Related allowance
With An Allowance Recorded	0	0
Total Impaired Loans	81	0
Average Recorded Investment
With No Related Allowance Recorded	0	123
With An Allowance Recorded	0	0
Loans Including Purchased Credit Impaired Loans	113	123
Consumer & other | Purchase credit impaired
Unpaid Contractual Principal Balance
Loans Including Purchased Credit Impaired Loans	192	0
Recorded investment
Loans Including Purchased Credit Impaired Loans	96	0
Related allowance
With An Allowance Recorded	81	0
Purchased Credit Impaired Loans	81	0
Average Recorded Investment
Loans Including Purchased Credit Impaired Loans	$ 113	$ 0