Loans (Aging of Past Due Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Loans	$ 3,007,926	$ 3,091,998		$ 3,081,973
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	3,182	5,219
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	808	7,545
Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	7,500	7,725
Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	11,490	20,489
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,996,436	3,071,509
Commercial and Industrial Loans
Financing Receivable, Past Due [Line Items]
Loans	493,005	638,773	$ 534,692	589,758
Commercial and Industrial Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	12	477
Commercial and Industrial Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	909
Commercial and Industrial Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	6,147	2,441
Commercial and Industrial Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	6,159	3,827
Commercial and Industrial Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	486,846	634,946
Commercial Real Estate Loans
Financing Receivable, Past Due [Line Items]
Loans	1,530,677	1,467,397	1,500,247	1,495,862
Commercial Real Estate Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	5
Commercial Real Estate Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	5	4,877
Commercial Real Estate Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	891	3,682
Commercial Real Estate Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	896	8,564
Commercial Real Estate Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,529,781	1,458,833
Agricultural Loans
Financing Receivable, Past Due [Line Items]
Loans	358,150	376,186	384,654	384,526
Agricultural Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Agricultural Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Agricultural Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	651
Agricultural Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	651
Agricultural Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	358,150	375,535
Leases
Financing Receivable, Past Due [Line Items]
Loans	55,345	55,664	57,257
Leases | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Leases | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Leases | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Leases | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Leases | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	55,345	55,664
Home Equity Loans
Financing Receivable, Past Due [Line Items]
Loans	222,525	219,348	225,790	225,755
Home Equity Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	225	672
Home Equity Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	229	5
Home Equity Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	25	271
Home Equity Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	479	948
Home Equity Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	222,046	218,400
Consumer Loans
Financing Receivable, Past Due [Line Items]
Loans	70,302	66,717	69,264	81,217
Consumer Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	158	233
Consumer Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	58	84
Consumer Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	4	65
Consumer Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	220	382
Consumer Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	70,082	66,335
Credit Cards
Financing Receivable, Past Due [Line Items]
Loans	14,357	11,637	11,953
Credit Cards | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	61	95
Credit Cards | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	9	80
Credit Cards | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	64	86
Credit Cards | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	134	261
Credit Cards | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	14,223	11,376
Residential Mortgage Loans
Financing Receivable, Past Due [Line Items]
Loans	263,565	256,276	$ 305,002	$ 304,855
Residential Mortgage Loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,726	3,737
Residential Mortgage Loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	507	1,590
Residential Mortgage Loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	369	529
Residential Mortgage Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans	3,602	5,856
Residential Mortgage Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Loans	$ 259,963	$ 250,420