LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR LOAN LOSSES (Schedule of Loans Receivable, Net) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 530,448	$ 523,001
Net deferred loan costs	83	104
Allowance for loan losses	(5,100)	(4,888)
Total loans receivable, net	525,431	518,217
One-to four-family residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	195,290	190,415
Allowance for loan losses	(707)	(731)
Commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	230,964	232,544
Allowance for loan losses	(1,919)	(2,066)
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	29,777	28,451
Allowance for loan losses	(574)	(511)
Home equity lines of credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	19,876	17,832
Allowance for loan losses	(140)	(138)
Commercial business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	49,729	48,769
Allowance for loan losses	(1,495)	(1,184)
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	4,812	4,990
Allowance for loan losses	$ (2)	$ (8)

Amount of deferred costs incurred to originate loans and leases from face amounts of acquired loans.

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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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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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