LOANS RECEIVABLE, NET (Schedule of Activity in the Allowance for Loan Losses by Loan Category) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	$ 6,400	$ 4,888
Charge-offs	(52)	(269)
Recoveries	98	115
Provision (credit)	1,629	1,666
Balance at the end of period	8,075	6,400
One-to four-family residential [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,035	731
Charge-offs
Recoveries	1	11
Provision (credit)	100	293
Balance at the end of period	1,136	1,035
Commercial real estate [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	3,232	2,066
Charge-offs	(51)
Recoveries		5
Provision (credit)	563	1,161
Balance at the end of period	3,744	3,232
Construction [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	672	511
Charge-offs		(65)
Recoveries
Provision (credit)	(78)	226
Balance at the end of period	594	672
Home equity lines of credit [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	179	138
Charge-offs
Recoveries	1
Provision (credit)	52	41
Balance at the end of period	232	179
Commercial business [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,034	1,184
Charge-offs		(204)
Recoveries	96	99
Provision (credit)	916	(45)
Balance at the end of period	2,046	1,034
Other [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1	8
Charge-offs	(1)
Recoveries
Provision (credit)	15	(7)
Balance at the end of period	15	1
Unallocated [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	247	250
Charge-offs
Recoveries
Provision (credit)	61	(3)
Balance at the end of period	$ 308	$ 247

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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