Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Statement of Financial Position [Abstract]
Investments securities held to maturity, estimated fair value	$ 265,092	$ 249,783
Allowance for loan losses	$ 14,698	$ 13,703
Preferred stock par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock shares authorized (shares)	1,000,000	1,000,000
Preferred stock shares issued (shares)	0	0
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock shares authorized (shares)	50,000,000	50,000,000
Common stock shares issued (shares)	8,203,174	8,221,952
Common stock shares outstanding (shares)	8,203,174	8,221,952

Face amount or stated value per share of common stock.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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