Loans - Past Due Receivables (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of past due loans [Abstract]
Total Past Due	$ 14,236	$ 18,913
Current	2,695,908	2,620,191
Ending balance	2,710,144	2,639,104	$ 2,627,943
Accruing Loans Past Due 90 Days or More	1,056	606
Agricultural [Member]
Schedule of past due loans [Abstract]
Total Past Due	1,067	560
Current	93,775	90,757
Ending balance	94,842	91,317	92,673
Accruing Loans Past Due 90 Days or More	111	48
Commercial and financial [Member]
Schedule of past due loans [Abstract]
Total Past Due	1,202	1,406
Current	285,040	219,917
Ending balance	286,242	221,323	229,501
Accruing Loans Past Due 90 Days or More	20	65
Construction, 1 to 4 family residential [Member]
Schedule of past due loans [Abstract]
Total Past Due	726	635
Current	70,391	79,574
Ending balance	71,117	80,209
Accruing Loans Past Due 90 Days or More	536	0
Construction, land development and commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	316
Current	111,913	108,094
Ending balance	111,913	108,410
Accruing Loans Past Due 90 Days or More	0	0
Mortgage, farmland [Member]
Schedule of past due loans [Abstract]
Total Past Due	307	1,346
Current	246,835	241,384
Ending balance	247,142	242,730	$ 236,454
Accruing Loans Past Due 90 Days or More	0	0
Mortgage, 1 to 4 family first liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	8,797	12,275
Current	883,292	898,467
Ending balance	892,089	910,742
Accruing Loans Past Due 90 Days or More	342	354
Mortgage, 1 to 4 family junior liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	612	1,172
Current	127,221	148,055
Ending balance	127,833	149,227
Accruing Loans Past Due 90 Days or More	47	139
Mortgage, multi-family [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	97
Current	374,014	350,664
Ending balance	374,014	350,761
Accruing Loans Past Due 90 Days or More	0	0
Mortgage, commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	1,244	810
Current	415,895	401,371
Ending balance	417,139	402,181
Accruing Loans Past Due 90 Days or More	0	0
Loans to individuals [Member]
Schedule of past due loans [Abstract]
Total Past Due	281	296
Current	31,044	32,012
Ending balance	31,325	32,308
Accruing Loans Past Due 90 Days or More	0	0
Obligations of state and political subdivisions [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
Current	56,488	49,896
Ending balance	56,488	49,896
Accruing Loans Past Due 90 Days or More	0	0
30 - 59 Days Past Due
Schedule of past due loans [Abstract]
Total Past Due	8,180	9,211
30 - 59 Days Past Due | Agricultural [Member]
Schedule of past due loans [Abstract]
Total Past Due	438	163
30 - 59 Days Past Due | Commercial and financial [Member]
Schedule of past due loans [Abstract]
Total Past Due	867	1,076
30 - 59 Days Past Due | Construction, 1 to 4 family residential [Member]
Schedule of past due loans [Abstract]
Total Past Due	190	635
30 - 59 Days Past Due | Construction, land development and commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	215
30 - 59 Days Past Due | Mortgage, farmland [Member]
Schedule of past due loans [Abstract]
Total Past Due	279	736
30 - 59 Days Past Due | Mortgage, 1 to 4 family first liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	4,969	5,026
30 - 59 Days Past Due | Mortgage, 1 to 4 family junior liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	436	813
30 - 59 Days Past Due | Mortgage, multi-family [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
30 - 59 Days Past Due | Mortgage, commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	783	321
30 - 59 Days Past Due | Loans to individuals [Member]
Schedule of past due loans [Abstract]
Total Past Due	218	226
30 - 59 Days Past Due | Obligations of state and political subdivisions [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
60 - 89 Days Past Due
Schedule of past due loans [Abstract]
Total Past Due	1,645	4,472
60 - 89 Days Past Due | Agricultural [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	275
60 - 89 Days Past Due | Commercial and financial [Member]
Schedule of past due loans [Abstract]
Total Past Due	195	229
60 - 89 Days Past Due | Construction, 1 to 4 family residential [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
60 - 89 Days Past Due | Construction, land development and commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	101
60 - 89 Days Past Due | Mortgage, farmland [Member]
Schedule of past due loans [Abstract]
Total Past Due	28	0
60 - 89 Days Past Due | Mortgage, 1 to 4 family first liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	1,342	3,100
60 - 89 Days Past Due | Mortgage, 1 to 4 family junior liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	21	126
60 - 89 Days Past Due | Mortgage, multi-family [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	97
60 - 89 Days Past Due | Mortgage, commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	489
60 - 89 Days Past Due | Loans to individuals [Member]
Schedule of past due loans [Abstract]
Total Past Due	59	55
60 - 89 Days Past Due | Obligations of state and political subdivisions [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
90 Days or More Past Due
Schedule of past due loans [Abstract]
Total Past Due	4,411	5,230
90 Days or More Past Due | Agricultural [Member]
Schedule of past due loans [Abstract]
Total Past Due	629	122
90 Days or More Past Due | Commercial and financial [Member]
Schedule of past due loans [Abstract]
Total Past Due	140	101
90 Days or More Past Due | Construction, 1 to 4 family residential [Member]
Schedule of past due loans [Abstract]
Total Past Due	536	0
90 Days or More Past Due | Construction, land development and commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
90 Days or More Past Due | Mortgage, farmland [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	610
90 Days or More Past Due | Mortgage, 1 to 4 family first liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	2,486	4,149
90 Days or More Past Due | Mortgage, 1 to 4 family junior liens [Member]
Schedule of past due loans [Abstract]
Total Past Due	155	233
90 Days or More Past Due | Mortgage, multi-family [Member]
Schedule of past due loans [Abstract]
Total Past Due	0	0
90 Days or More Past Due | Mortgage, commercial [Member]
Schedule of past due loans [Abstract]
Total Past Due	461	0
90 Days or More Past Due | Loans to individuals [Member]
Schedule of past due loans [Abstract]
Total Past Due	4	15
90 Days or More Past Due | Obligations of state and political subdivisions [Member]
Schedule of past due loans [Abstract]
Total Past Due	$ 0	$ 0