Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Investments securities held to maturity, estimated fair value	$ 38,332	$ 32,580
Allowance for loan losses	$ 11,890	$ 9,690
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)	8,309,193	8,329,419
Common stock shares outstanding (shares)	8,309,193	8,329,419

Face amount or stated value per share of common stock.

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