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Loans and Allowance for Credit Losses - Performing Loans Classified as Troubled Debt Restructuring Loans (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan | Jun. 30, 2021 USD ($) loan
Number of modifications | loan | 1 | 4 |
Recorded Investment | $ | $ 151 | $ 1,974 |
Performing Loans |  |  |
Number of modifications | loan | 15 |  | 12
Recorded Investment | $ | $ 3,585 |  | $ 3,241
Residential Real Estate |  |  |
Number of modifications | loan | 1 | 1 |
Recorded Investment | $ | $ 151 | $ 98 |
Residential Real Estate | Performing Loans |  |  |
Number of modifications | loan | 3 |  | 1
Recorded Investment | $ | $ 1,133 |  | $ 895
Commercial Real Estate |  |  |
Number of modifications | loan |  | 2 |
Recorded Investment | $ |  | $ 1,840 |
Commercial Real Estate | Performing Loans |  |  |
Number of modifications | loan | 5 |  | 4
Recorded Investment | $ | $ 988 |  | $ 949
Commercial loans |  |  |
Number of modifications | loan |  | 1 |
Recorded Investment | $ |  | $ 36 |
Commercial loans | Performing Loans |  |  |
Number of modifications | loan | 7 |  | 7
Recorded Investment | $ | $ 1,464 |  | $ 1,397

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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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