LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR LOAN LOSSES (Schedule of Loans Receivable, Net) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 607,030	$ 611,259
Net deferred loan costs	(1,370)	(1,749)
Allowance for loan losses	(7,130)	(6,400)
Total loans receivable, net	598,530	603,110
One-to four-family residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	208,404	210,360
Allowance for loan losses	(1,155)	(1,035)
Commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	260,296	248,134
Allowance for loan losses	(3,408)	(3,232)
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	23,441	28,242
Allowance for loan losses	(470)	(672)
Home equity lines of credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	19,837	19,373
Allowance for loan losses	(267)	(179)
Commercial business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	91,215	100,993
Allowance for loan losses	(1,716)	(1,034)
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	3,837	4,157
Allowance for loan losses	$ (2)	$ (1)

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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