LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR LOAN LOSSES (Schedule of Loans Receivable, Net) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	$ 612,469	$ 523,001
Net deferred loan costs	(1,919)	104
Allowance for loan losses	(6,000)	(4,888)
Total loans receivable, net	604,550	518,217
One-to four-family residential [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	213,415	190,415
Allowance for loan losses	(1,069)	(731)
Commercial real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	249,148	232,544
Allowance for loan losses	(2,617)	(2,066)
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	23,350	28,451
Allowance for loan losses	(687)	(511)
Home equity lines of credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	20,821	17,832
Allowance for loan losses	(182)	(138)
Commercial business [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	101,081	48,769
Allowance for loan losses	(1,261)	(1,184)
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans receivable	4,654	4,990
Allowance for loan losses	$ (1)	$ (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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