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	6 Months Ended
Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2018	Mar. 31, 2017
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	$ 3,537	$ 3,475	$ 3,170	$ 3,056	$ 3,475	$ 3,056
Charge-offs	(25)	(297)	(278)	(255)
Recoveries		109	18	39
Provision	257	250	403	330	506	733
Balance at the end of period	3,769	3,537	3,313	3,170	3,769	3,313
One-to four-family residential [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	563	587	524	542	587	542
Charge-offs	(25)	(127)	(52)	(18)
Recoveries		82		35
Provision	(5)	21	175	(35)
Balance at the end of period	533	563	647	524	533	647
Commercial real estate [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,299	1,277	1,152	1,075	1,277	1,075
Charge-offs
Recoveries		23
Provision	119	(1)	(44)	77
Balance at the end of period	1,418	1,299	1,108	1,152	1,418	1,108
Construction [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	384	490	368	361	490	361
Charge-offs
Recoveries		3	3	3
Provision	58	(109)	(3)	4
Balance at the end of period	442	384	368	368	442	368
Home equity lines of credit [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	131	57	71	71	57	71
Charge-offs
Recoveries			14
Provision	(19)	74	(18)
Balance at the end of period	112	131	67	71	112	67
Commercial business [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	1,052	956	914	976	956	976
Charge-offs		(170)	(226)	(237)
Recoveries		1	1	1
Provision	106	265	323	174
Balance at the end of period	1,158	1,052	1,012	914	1,158	1,012
Other [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	4	6	7	9	6	9
Charge-offs
Recoveries
Provision		(2)	6	(2)
Balance at the end of period	4	4	13	7	4	13
Unallocated [Member]
Activity in the allowance for loan losses by loan category:
Balance at beginning of period	104	102	134	22	102	22
Charge-offs
Recoveries
Provision	(2)	2	(36)	112
Balance at the end of period	$ 102	$ 104	$ 98	$ 134	$ 102	$ 98

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.

+ References

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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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