Loans and Allowance for Credit Losses - Restructured Loans that are Considered to be in Default (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) Contract	Dec. 31, 2020 USD ($) Contract	Dec. 31, 2019 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	2	3	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 244	$ 108	$ 0
Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	0	1	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 0	$ 34	$ 0
Loans To Individuals [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	1	2	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 21	$ 74	$ 0
Commercial Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	1	0	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 223	$ 0	$ 0
Automobiles \| Loans To Individuals [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	1	2
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 21	$ 74
Time and demand loans \| Commercial Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	1	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 223	$ 0
Junior Lien \| Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| Contract	0	1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default \| $	$ 0	$ 34

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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