Loan Servicing Rights - Summary of Loans serviced for Freddie Mac (Details) - Freddie Mac - USD ($) $ in Thousands	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Servicing Assets at Fair Value [Line Items]
Loans serviced for Freddie Mac, Principal amount	$ 384,619	$ 406,727	$ 419,675
Loans serviced for SBA, Principal amount	$ 1,882	$ 3,560	$ 6,761

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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