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Derivatives and Hedging Activities - Narrative (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Derivative [Line Items] |  |
Gain (loss) recognized on cash flow hedges | $ 0 | $ 0
Related Party Loan |  |
Derivative [Line Items] |  |
Outstanding notional balance | $ 34,283,000 |
Minimum |  |
Derivative [Line Items] |  |
Derivative maturities | 1 year |
Maximum |  |
Derivative [Line Items] |  |
Derivative maturities | 10 years |
Weighted average |  |
Derivative [Line Items] |  |
Derivative maturities | 6 years 8 months 12 days |

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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