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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, 2020 | Sep. 30, 2019
--- | --- | ---
Nonaccruing Loans [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure | $ 13,001 |  | $ 9,810 |
Real estate and other repossessed assets [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure | 2,993 |  | 936 |
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 | 13,001 |  | 9,810 |
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 |  |  |
Appraised Value, as Adjusted [Member] | Real estate and other repossessed assets [Member] | Marketability adjustments off appraised value |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Assets, Fair Value Disclosure |  |  | $ 936 |
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 | 0.00% | [1] | 8.00% | [2]
Minimum [Member] | Real estate and other repossessed assets [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value Measurement, Percentage of Appraised Value. |  |  | 75.00% |
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 | 73.00% | [1] | 76.00% | [2]
Maximum [Member] | Real estate and other repossessed assets [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value Measurement, Percentage of Appraised Value. |  |  | 89.00% |
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 | 18.00% | [1] | 28.00% | [2]
Weighted Average [Member] | Real estate and other repossessed assets [Member] |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |  |
Fair Value Measurement, Percentage of Appraised Value. |  |  | 85.00% |
[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 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=117815213&loc=d3e19207-110258 + Details
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