Loans, Past Due (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Recorded investment of past due [Abstract]
Total past due	$ 2,239,659	$ 2,248,836
90 days or greater past due and accruing	820	516
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	14,693	12,187
Nonaccrual With a related allowance	3,614	4,398
Nonaccrual Without a related allowance	11,079	7,789
90 days or greater past due and accruing	820	516
Total non-performing loans	15,513	12,703
Financing receivables on accrual status [Abstract]
Total financing receivables and still accruing	$ 2,224,966	2,236,649
Minimum [Member]
Financing receivables on nonaccrual status [Abstract]
Period of past due after which loans considered as non accrual	90 days
Current [Member]
Recorded investment of past due [Abstract]
Total past due	$ 2,220,134	2,229,685
Financing receivables on nonaccrual status [Abstract]
Current and non-accrual	2,299	4,008
Financing receivable nonaccrual status	2,220,134	2,229,685
Financing receivables on accrual status [Abstract]
Current and still accruing	2,217,835	2,225,677
Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	19,525	19,151
Financing receivables on nonaccrual status [Abstract]
Total past due and non-accrual	12,394	8,179
Financing receivables on accrual status [Abstract]
Total past due and still accruing	7,131	10,972
30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	5,238	9,251
Financing receivables on nonaccrual status [Abstract]
Total past due and non-accrual	296	199
Financing receivables on accrual status [Abstract]
Total past due and still accruing	4,942	9,052
60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	1,765	2,070
Financing receivables on nonaccrual status [Abstract]
Total past due and non-accrual	396	666
Financing receivables on accrual status [Abstract]
Total past due and still accruing	1,369	1,404
90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	12,522	7,830
Financing receivables on nonaccrual status [Abstract]
Total past due and non-accrual	11,702	7,314
Financing receivables on accrual status [Abstract]
Total past due and still accruing	820	516
Home Equity [Member]
Recorded investment of past due [Abstract]
Total past due	49,190	49,791
Commercial [Member]
Recorded investment of past due [Abstract]
Total past due	1,115,900	1,092,887
Construction [Member]
Recorded investment of past due [Abstract]
Total past due	184,506	195,826
Real Estate Loans [Member] | Mortgages [Member]
Recorded investment of past due [Abstract]
Total past due	308,589	310,199
90 days or greater past due and accruing	565	0
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	2,891	2,961
Nonaccrual With a related allowance	311	315
Nonaccrual Without a related allowance	2,580	2,646
90 days or greater past due and accruing	565	0
Total non-performing loans	3,456	2,961
Real Estate Loans [Member] | Mortgages [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	304,256	304,917
Real Estate Loans [Member] | Mortgages [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	4,333	5,282
Real Estate Loans [Member] | Mortgages [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	1,412	2,682
Real Estate Loans [Member] | Mortgages [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	576	360
Real Estate Loans [Member] | Mortgages [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	2,345	2,240
Real Estate Loans [Member] | Home Equity [Member]
Recorded investment of past due [Abstract]
Total past due	49,190	49,791
90 days or greater past due and accruing	0	18
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	119	121
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	119	121
90 days or greater past due and accruing	0	18
Total non-performing loans	119	139
Real Estate Loans [Member] | Home Equity [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	48,891	49,508
Real Estate Loans [Member] | Home Equity [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	299	283
Real Estate Loans [Member] | Home Equity [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	180	145
Real Estate Loans [Member] | Home Equity [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	67
Real Estate Loans [Member] | Home Equity [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	119	71
Real Estate Loans [Member] | Commercial [Member]
Recorded investment of past due [Abstract]
Total past due	1,115,900	1,092,887
90 days or greater past due and accruing	243	404
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	2,485	1,135
Nonaccrual With a related allowance	1,265	256
Nonaccrual Without a related allowance	1,220	879
90 days or greater past due and accruing	243	404
Total non-performing loans	2,728	1,539
Real Estate Loans [Member] | Commercial [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	1,112,357	1,090,111
Real Estate Loans [Member] | Commercial [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	3,543	2,776
Real Estate Loans [Member] | Commercial [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	889	1,151
Real Estate Loans [Member] | Commercial [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	185	245
Real Estate Loans [Member] | Commercial [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	2,469	1,380
Real Estate Loans [Member] | Agricultural [Member]
Recorded investment of past due [Abstract]
Total past due	318,413	314,802
90 days or greater past due and accruing	0	75
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	2,608	2,670
Nonaccrual With a related allowance	181	181
Nonaccrual Without a related allowance	2,427	2,489
90 days or greater past due and accruing	0	75
Total non-performing loans	2,608	2,745
Real Estate Loans [Member] | Agricultural [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	316,872	313,290
Real Estate Loans [Member] | Agricultural [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	1,541	1,512
Real Estate Loans [Member] | Agricultural [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	175	72
Real Estate Loans [Member] | Agricultural [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	0
Real Estate Loans [Member] | Agricultural [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	1,366	1,440
Real Estate Loans [Member] | Construction [Member]
Recorded investment of past due [Abstract]
Total past due	184,506	195,826
90 days or greater past due and accruing	0	0
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	4,283	2,357
Nonaccrual With a related allowance	0	2,357
Nonaccrual Without a related allowance	4,283	0
90 days or greater past due and accruing	0	0
Total non-performing loans	4,283	2,357
Real Estate Loans [Member] | Construction [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	180,223	188,674
Real Estate Loans [Member] | Construction [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	4,283	7,152
Real Estate Loans [Member] | Construction [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	4,407
Real Estate Loans [Member] | Construction [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	388
Real Estate Loans [Member] | Construction [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	4,283	2,357
Consumer [Member]
Recorded investment of past due [Abstract]
Total past due	53,101	61,316
90 days or greater past due and accruing	12	13
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	849	701
Nonaccrual With a related allowance	849	701
Nonaccrual Without a related allowance	0	0
90 days or greater past due and accruing	12	13
Total non-performing loans	861	714
Consumer [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	51,906	60,995
Consumer [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	1,195	321
Consumer [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	209	16
Consumer [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	125	282
Consumer [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	861	23
Other Commercial Loans [Member]
Recorded investment of past due [Abstract]
Total past due	129,438	136,168
90 days or greater past due and accruing	0	6
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	1,028	1,750
Nonaccrual With a related allowance	1,008	588
Nonaccrual Without a related allowance	20	1,162
90 days or greater past due and accruing	0	6
Total non-performing loans	1,028	1,756
Other Commercial Loans [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	125,327	134,813
Other Commercial Loans [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	4,111	1,355
Other Commercial Loans [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	2,344	670
Other Commercial Loans [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	879	366
Other Commercial Loans [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	888	319
Other Agricultural Loans [Member]
Recorded investment of past due [Abstract]
Total past due	24,345	30,673
90 days or greater past due and accruing	0	0
Financing receivables on nonaccrual status [Abstract]
Financing receivable nonaccrual status	430	492
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	430	492
90 days or greater past due and accruing	0	0
Total non-performing loans	430	492
Other Agricultural Loans [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	24,125	30,203
Other Agricultural Loans [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	220	470
Other Agricultural Loans [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	29	108
Other Agricultural Loans [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	362
Other Agricultural Loans [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	191	0
State and Political Subdivision Loans [Member]
Recorded investment of past due [Abstract]
Total past due	56,177	57,174
90 days or greater past due and accruing	0	0
Financing receivables on nonaccrual status [Abstract]
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	0	0
90 days or greater past due and accruing	0	0
Total non-performing loans	0	0
State and Political Subdivision Loans [Member] | Current [Member]
Recorded investment of past due [Abstract]
Total past due	56,177	57,174
State and Political Subdivision Loans [Member] | Total Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	0
State and Political Subdivision Loans [Member] | 30 to 59 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	0
State and Political Subdivision Loans [Member] | 60 to 89 Days Past Due [Member]
Recorded investment of past due [Abstract]
Total past due	0	0
State and Political Subdivision Loans [Member] | 90 Days Or Greater [Member]
Recorded investment of past due [Abstract]
Total past due	$ 0	$ 0