INVESTMENT SECURITIES (Summary of Maturities of Debt Securities and Mortgage-backed Securities Held to Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	$ 48,298	$ 30,443
Gross Unrealized Gains	474	709
Gross Unrealized Losses	(509)	(253)
Fair Value	48,263	30,899
Obligations of U.S. government agencies Mortgage backed securities - residential [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	753	1,453
Gross Unrealized Gains		11
Gross Unrealized Losses	(29)	(33)
Fair Value	724	1,431
Obligations of U.S. government agencies Mortgage backed securities -commercial [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	721	775
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	721	775
Obligations of U.S. government-sponsored enterprises Mortgage-backed securities-residential [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	30,035	20,456
Gross Unrealized Gains	470	697
Gross Unrealized Losses	(138)	(3)
Fair Value	30,367	21,150
Obligations of U.S. government-sponsored enterprises Debt securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	12,498	4,500
Gross Unrealized Gains		1
Gross Unrealized Losses	(141)	(16)
Fair Value	12,357	4,485
Private label mortgage-backed securities-residential [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	247	259
Gross Unrealized Gains	4
Gross Unrealized Losses		(5)
Fair Value	251	254
Obligations of state and political subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	1,044
Gross Unrealized Gains
Gross Unrealized Losses	(4)
Fair Value	1,040
Corporate securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	3,000	3,000
Gross Unrealized Gains
Gross Unrealized Losses	(197)	(196)
Fair Value	$ 2,803	$ 2,804

Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
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-URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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