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, 2018	Dec. 31, 2017
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	$ 4,200	$ 3,475
Charge-offs		(297)
Recoveries	1	109
Provision	201	250
Balance at the end of period	4,402	3,537
One-to four-family residential [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	687	587
Charge-offs		(127)
Recoveries		82
Provision	11	21
Balance at the end of period	698	563
Commercial real estate [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,540	1,277
Charge-offs
Recoveries		23
Provision	50	(1)
Balance at the end of period	1,590	1,299
Construction [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	493	490
Charge-offs
Recoveries		3
Provision	181	(109)
Balance at the end of period	674	384
Home equity lines of credit [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	109	57
Charge-offs
Recoveries	1
Provision	11	74
Balance at the end of period	121	131
Commercial business [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,151	956
Charge-offs		(170)
Recoveries		1
Provision	31	265
Balance at the end of period	1,182	1,052
Other [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	25	6
Charge-offs
Recoveries
Provision	(21)	(2)
Balance at the end of period	4	4
Unallocated [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	195	102
Charge-offs
Recoveries
Provision	(62)	2
Balance at the end of period	$ 133	$ 104

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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