LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR LOAN LOSSES (Schedule of Activity in the Allowance for Loan Losses by Loan Category) (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	$ 6,400	$ 4,888
Charge-offs
Recoveries	90	2
Provision (credit)	640	210
Balance at the end of period	7,130	5,100
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		2
Provision (credit)	120	(26)
Balance at the end of period	1,155	707
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
Recoveries
Provision (credit)	176	(147)
Balance at the end of period	3,408	1,919
Construction [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	672	511
Charge-offs
Recoveries
Provision (credit)	(202)	63
Balance at the end of period	470	574
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
Provision (credit)	88	2
Balance at the end of period	267	140
Commercial business [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,034	1,184
Charge-offs
Recoveries	90
Provision (credit)	592	311
Balance at the end of period	1,716	1,495
Other [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1	8
Charge-offs
Recoveries
Provision (credit)	1	(6)
Balance at the end of period	2	2
Unallocated [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	247	250
Charge-offs
Recoveries
Provision (credit)	(135)	13
Balance at the end of period	$ 112	$ 263

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

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