Represents the amortized cost of the loans outstanding related to the PPP (paycheck protection program).

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Represents the limit of loan above which loans are reviewed annually.

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Represents the limit of loan where loans are processed through an expedited underwriting process.

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No definition available.

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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.

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Amount of increase (decrease) of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Unearned discounts (other than cash or quantity discounts and the like), finance charges, and interest included in the face amount of receivables, that are shown as a deduction from the related receivables. For example, 1) finance charges booked as a receivable when a loan is made and recognized as income at a later date; and 2) interest charges deducted from the face loan amount, resulting in a discounted amount actually advanced to the borrower (wherein the receivable includes the amount actually advanced to the borrower and the as yet unearned interest income).

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of increase from purchase of financing receivable.

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Amount of unamortized loan commitment, origination, and other fees (costs) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Portfolio Loans - Narrative (Details) $ in Thousands	3 Months Ended				9 Months Ended	12 Months Ended
Portfolio Loans - Narrative (Details) $ in Thousands	Mar. 31, 2022 USD ($) loan	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($) loan	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Distributions of portfolio loans
Net deferred loan origination (fees) costs						$ 9,000
Net deferred loan origination costs	$ 10,600
Net accretable purchase accounting adjustments	7,700					8,800
Gross interest income that would have been recorded if impaired loans had been current	$ 200		$ 500
Amount of interest collected and recognized on a cash basis		$ 400			$ 400
TDRs subsequently classified as non-performing and had payment defaults \| loan	0		0
Loans in the process of foreclosure	$ 500
Retail real estate
Distributions of portfolio loans
Loans purchased		$ 0		$ 0
Maximum \| Commercial Real Estate Loans
Distributions of portfolio loans
Limit where loans are processed through an expedited underwriting process	1,000
Watch \| Commercial Loans
Distributions of portfolio loans
Limit above which loans are annually reviewed	1,000
Special Mention \| Commercial Loans
Distributions of portfolio loans
Limit above which loans are annually reviewed	350
PPP Loans
Distributions of portfolio loans
Amortized cost of the loans outstanding	$ 31,800					$ 75,000