SECURITIES - Held to Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Total securities HTM, at cost	$ 72,112	$ 92,610
Gross Unrealized Gains	1,182	1,164
Gross Unrealized (Losses)	0	(29)
Fair Value	73,294	93,745
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
LESS THAN 12 MONTHS, Fair Value		7,397
LESS THAN 12 MONTHS, Gross Unrealized (Losses)		(9)
OVER 12 MONTHS, Fair Value		3,637
OVER 12 MONTHS, Gross Unrealized (Losses)		(20)
TOTAL, Fair Value		11,034
TOTAL, Gross Unrealized (Losses)		(29)
Amortized Cost
Due after ten years	67,709	87,183
Total	67,709	87,183
Mortgage-backed securities	4,403	5,427
Total securities HTM, at cost	72,112	92,610
Fair Value
Due after ten years	68,792	88,194
Total	68,792	88,194
Mortgage-backed securities	4,502	5,551
Fair Value	73,294	93,745
Non-bank qualified obligations of states and political subdivisions
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Total securities HTM, at cost	67,709	87,183
Gross Unrealized Gains	1,083	1,040
Gross Unrealized (Losses)	0	(29)
Fair Value	68,792	88,194
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
LESS THAN 12 MONTHS, Fair Value		7,397
LESS THAN 12 MONTHS, Gross Unrealized (Losses)		(9)
OVER 12 MONTHS, Fair Value		3,637
OVER 12 MONTHS, Gross Unrealized (Losses)		(20)
TOTAL, Fair Value		11,034
TOTAL, Gross Unrealized (Losses)		(29)
Amortized Cost
Total securities HTM, at cost	67,709	87,183
Fair Value
Fair Value	68,792	88,194
Mortgage-backed securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Total securities HTM, at cost	4,403	5,427
Gross Unrealized Gains	99	124
Gross Unrealized (Losses)	0	0
Fair Value	4,502	5,551
Amortized Cost
Total securities HTM, at cost	4,403	5,427
Fair Value
Fair Value	$ 4,502	$ 5,551

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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), in continuous loss position for 12 months or longer.

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