Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) Modifications	Dec. 31, 2020 USD ($) Modifications	Dec. 31, 2019 USD ($) Modifications
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	16	19	24
Pre-Modification Outstanding Recorded Investment	$ 3,966	$ 7,566	$ 7,348
Post-Modification Outstanding Recorded Investment	$ 3,966	$ 7,566	$ 7,348
Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	1	0	0
Pre-Modification Outstanding Recorded Investment	$ 628	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 628	$ 0	$ 0
Commercial Business
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	11	11	10
Pre-Modification Outstanding Recorded Investment	$ 2,600	$ 3,257	$ 6,560
Post-Modification Outstanding Recorded Investment	$ 2,600	$ 3,257	$ 6,560
Agriculture
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	1	2	0
Pre-Modification Outstanding Recorded Investment	$ 583	$ 3,495	$ 0
Post-Modification Outstanding Recorded Investment	$ 583	$ 3,495	$ 0
Real estate: One-to-four family residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	3	6	13
Pre-Modification Outstanding Recorded Investment	$ 155	$ 814	$ 787
Post-Modification Outstanding Recorded Investment	$ 155	$ 814	$ 787
Consumer Loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDR Modifications, Number of Contracts \| Modifications	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 1

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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