Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Statement of Financial Position [Abstract]
Fair value of investment securities - held to maturity	$ 32,905	$ 51,241
Allowance for loan losses	$ 3,985	$ 3,475
Preferred stock; par value	$ 0.01	$ 0.01
Preferred stock; shares authorized	1,000,000	1,000,000
Preferred stock; shares issued	0	0
Common stock; par value	$ 0.01	$ 0.01
Common stock; shares authorized	8,000,000	8,000,000
Common stock; shares issued	5,923,742	5,923,742
Common stock, shares outstanding	5,820,746	5,820,746
Treasury stock, shares	102,996	102,996

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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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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