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Fair Value Accounting and Measurement (Quantitative Information About Level 3 Fair Value Measurements) (Details) - Fair Value, Nonrecurring [Member] $ in Thousands | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($)
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Fair Value Measurements Inputs and Valuation Techniques |  |
Collateral dependent loans, Fair Value | $ 1,845 | $ 11,899
Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Measurements Inputs and Valuation Techniques |  |
Collateral dependent loans, Fair Value | $ 1,845 | $ 11,899
Valuation, Market Approach [Member] | Minimum [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Measurements Inputs and Valuation Techniques |  |
Collateral dependent loans, Measurement Input | 0.0000 | 0.0000
Valuation, Market Approach [Member] | Maximum [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Measurements Inputs and Valuation Techniques |  |
Collateral dependent loans, Measurement Input | 0.9746 | 1.0000
Valuation, Market Approach [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Measurements Inputs and Valuation Techniques |  |
Collateral dependent loans, Measurement Input | 0.7144 | 0.1557

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