Loans Loans (Analysis of Troubled Debt Restructurings) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) Modifications	Sep. 30, 2019 USD ($) Modifications	Sep. 30, 2020 USD ($) Modifications	Sep. 30, 2019 USD ($) Modifications
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	9	11	18	21
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 4,013	$ 5,384	$ 7,066	$ 7,253
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 4,013	$ 5,384	$ 7,066	$ 7,253
Commercial Business [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	4	5	10	10
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 795	$ 5,026	$ 2,757	$ 6,560
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 795	$ 5,026	$ 2,757	$ 6,560
Agriculture [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	1	0	2	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 2,600	$ 0	$ 3,495	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 2,600	$ 0	$ 3,495	$ 0
One-to-Four Family Residential [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	4	5	6	10
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 618	$ 357	$ 814	$ 692
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 618	$ 357	$ 814	$ 692
Consumer Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Modifications	0	1	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 1	$ 0	$ 1
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 1	$ 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=121611835&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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