Employee Benefit Plans (Summary of Pentegra Plans) (Details) - Pentegra Defined Benefit Plan for Financial Institutions	Dec. 31, 2020
Classic Bancshares, Inc. [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined Benefit Plan, Funded Percentage	89.16%
Poage Bankshares, Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined Benefit Plan, Funded Percentage	91.56%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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