LOANS RECEIVABLE, NET (Schedule of Activity in the Allowance for Loan Losses by Loan Category) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	$ 4,888	$ 4,200
Charge-offs	(269)	(101)
Recoveries	115	121
Provision (credit)	1,666	668
Balance at the end of period	6,400	4,888
One-to four-family residential [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	731	687
Charge-offs
Recoveries	11	120
Provision (credit)	293	(76)
Balance at the end of period	1,035	731
Commercial real estate [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	2,066	1,540
Charge-offs		(1)
Recoveries	5
Provision (credit)	1,161	527
Balance at the end of period	3,232	2,066
Construction [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	511	493
Charge-offs	(65)
Recoveries
Provision (credit)	226	18
Balance at the end of period	672	511
Home equity lines of credit [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	138	109
Charge-offs
Recoveries		1
Provision (credit)	41	28
Balance at the end of period	179	138
Commercial business [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,184	1,151
Charge-offs	(204)	(100)
Recoveries	99
Provision (credit)	(45)	133
Balance at the end of period	1,034	1,184
Other [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	8	25
Charge-offs
Recoveries
Provision (credit)	(7)	(17)
Balance at the end of period	1	8
Unallocated [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	250	195
Charge-offs
Recoveries
Provision (credit)	(3)	55
Balance at the end of period	$ 247	$ 250

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

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