Loans (Risk Category of Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	$ 3,007,926	$ 3,091,998		$ 3,081,973
Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	141,348	260,788
2020-2019	58,826	89,539
2019-2018	61,110	50,720
2018-2017	30,716	34,881
2017-2016	17,321	21,838
Prior	51,934	55,896
Revolving Loans Amortized Cost Basis	131,750	125,111
Loans	493,005	638,773	$ 534,692	589,758
Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	406,528	297,148
2020-2019	264,011	225,718
2019-2018	172,601	196,096
2018-2017	147,700	208,884
2017-2016	157,144	182,886
Prior	355,996	326,784
Revolving Loans Amortized Cost Basis	26,697	29,881
Loans	1,530,677	1,467,397	1,500,247	1,495,862
Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	46,224	61,323
2020-2019	50,447	35,433
2019-2018	28,048	34,790
2018-2017	27,597	42,363
2017-2016	31,811	29,875
Prior	84,741	80,213
Revolving Loans Amortized Cost Basis	89,282	92,189
Loans	358,150	376,186	384,654	$ 384,526
Leases
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	19,689	18,258
2020-2019	12,706	17,517
2019-2018	12,990	9,176
2018-2017	5,599	5,415
2017-2016	2,473	1,605
Prior	1,888	3,693
Revolving Loans Amortized Cost Basis	0	0
Loans	55,345	55,664	$ 57,257
Pass \| Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	141,133	260,027
2020-2019	57,477	88,273
2019-2018	60,883	46,681
2018-2017	29,005	31,612
2017-2016	15,936	21,025
Prior	48,559	48,508
Revolving Loans Amortized Cost Basis	122,377	109,228
Loans	475,370	605,354
Pass \| Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	404,175	296,265
2020-2019	264,011	215,226
2019-2018	164,204	179,129
2018-2017	131,746	183,703
2017-2016	139,788	171,016
Prior	336,066	295,641
Revolving Loans Amortized Cost Basis	26,697	29,634
Loans	1,466,687	1,370,614
Pass \| Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	44,510	49,242
2020-2019	45,101	25,449
2019-2018	22,482	31,285
2018-2017	24,187	32,368
2017-2016	24,325	22,702
Prior	71,268	64,890
Revolving Loans Amortized Cost Basis	81,011	75,871
Loans	312,884	301,807
Pass \| Leases
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	19,689	18,258
2020-2019	12,706	17,517
2019-2018	12,990	9,176
2018-2017	5,599	5,415
2017-2016	2,473	1,605
Prior	1,888	3,693
Revolving Loans Amortized Cost Basis	0	0
Loans	55,345	55,664
Special Mention \| Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	115	618
2020-2019	128	1,102
2019-2018	227	2,756
2018-2017	649	1,739
2017-2016	7	206
Prior	918	1,972
Revolving Loans Amortized Cost Basis	1,510	9,948
Loans	3,554	18,341
Special Mention \| Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	2,279	883
2020-2019	0	9,361
2019-2018	710	15,232
2018-2017	14,426	23,489
2017-2016	17,356	7,578
Prior	13,916	20,294
Revolving Loans Amortized Cost Basis	0	147
Loans	48,687	76,984
Special Mention \| Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	1,714	11,503
2020-2019	5,346	9,911
2019-2018	5,503	3,111
2018-2017	3,025	8,767
2017-2016	6,438	2,707
Prior	6,624	10,125
Revolving Loans Amortized Cost Basis	8,271	16,318
Loans	36,921	62,442
Special Mention \| Leases
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	0	0
Substandard \| Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	100	143
2020-2019	1,221	164
2019-2018	0	1,283
2018-2017	1,062	1,530
2017-2016	1,378	607
Prior	2,457	5,416
Revolving Loans Amortized Cost Basis	7,863	5,935
Loans	14,081	15,078
Substandard \| Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	74	0
2020-2019	0	1,131
2019-2018	7,687	1,735
2018-2017	1,528	1,692
2017-2016	0	4,292
Prior	6,014	10,849
Revolving Loans Amortized Cost Basis	0	100
Loans	15,303	19,799
Substandard \| Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	578
2020-2019	0	73
2019-2018	63	394
2018-2017	385	1,228
2017-2016	1,048	4,466
Prior	6,849	5,198
Revolving Loans Amortized Cost Basis	0	0
Loans	8,345	11,937
Substandard \| Leases
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	0	0
Doubtful \| Commercial and Industrial Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	0	0
Doubtful \| Commercial Real Estate Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	0	0
Doubtful \| Agricultural Loans
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	0	0
Doubtful \| Leases
Financing Receivable, Credit Quality Indicator [Line Items]
2021-2020	0	0
2020-2019	0	0
2019-2018	0	0
2018-2017	0	0
2017-2016	0	0
Prior	0	0
Revolving Loans Amortized Cost Basis	0	0
Loans	$ 0	$ 0

Amount, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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