Goodwill and CDI - CDI (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Finite-Lived Intangible Assets [Line Items]
Amortization of CDI	$ 180	$ 226	$ 271
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Amortization of CDI	$ 180	$ 226	$ 271

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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+ Details

- 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.

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+ Details