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v3.21.1

Derivatives and Hedging Activities - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2021 | Mar. 31, 2020
Derivative [Line Items] |  |  |  |
Gain (loss) on termination of hedging derivatives | $ 14,110 | $ 0 | $ 14,110 | $ 0
Interest Rate Swap One | Cash flow hedging | Designated as Hedging Instrument |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amount of derivative terminated |  |  | $ 200,000 |
Effective interest rate of derivative terminated |  |  | 1.37% |
Interest Rate Swap | Minimum |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, maturities |  |  | 1 year |
Interest Rate Swap | Maximum |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, maturities |  |  | 10 years |
Interest Rate Swap | Weighted average |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, maturities |  |  | 6 years 8 months 12 days |
Interest Rate Swap Two | Cash flow hedging | Designated as Hedging Instrument |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amount of derivative terminated |  |  | $ 200,000 |
Effective interest rate of derivative terminated |  |  | 0.79% |
Interest Rate Swap Three | Not Designated as Hedging Instrument |  |  |  |
Derivative [Line Items] |  |  |  |
Notional amount of derivative terminated |  |  | $ 150,000 |
Effective interest rate of derivative terminated |  |  | 2.91% |

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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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- Definition Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Change in carrying amount of the indemnification asset relating to loss sharing agreements with the Federal Deposit Insurance Corporation (FDIC). The change includes for example, but is not limited to, acquisitions, additional estimated losses, disposals, cash payments, accretion of discount and write-offs, net of recoveries. + References No definition available. + Details
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