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Fair Value Measurements Fair Value Measurement, Measured On Non-Recurring Basis, Signfiicant Unobservable Inputs, Quantitative Information (Details) - Fair Value, Nonrecurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands | Sep. 30, 2021 | Sep. 30, 2020
--- | --- | ---
Nonaccruing Loans [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure | $ 12,538 |  | $ 13,001 |
Real estate and other repossessed assets [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure | 0 |  | 2,993 |
Discounted Cash Flow [Member] | Nonaccruing Loans [Member] | Management knowledge of Industry [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure | $ 12,538 |  | 13,001 |
Discounted Cash Flow [Member] | Real estate and other repossessed assets [Member] | Management knowledge of Industry [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure |  |  | $ 2,993 |
Minimum [Member] | Nonaccruing Loans [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 1.00% | [1] | 0.00% | [2]
Maximum [Member] | Nonaccruing Loans [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 97.00% | [1] | 73.00% | [2]
Weighted Average [Member] | Nonaccruing Loans [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 23.00% | [1] | 18.00% | [2]
[1] | Represents fair value as a percentage of the unpaid principal balance.
[2] | Represents fair value as a percentage of the unpaid principal balance.

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- Definition Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition 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. + References No definition available. + Details
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