INVESTMENT SECURITIES - Schedule of Amortized Cost and Fair Values of Securities Held to Maturity (Details) - Debt Securities [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2024	Sep. 30, 2024
Securities available-for-sale:
Securities Available-For-Sale, Amortized Cost	$ 18,714	$ 16,747
Securities Available-For-Sale, Gross Unrealized Gains	133	77
Securities Available-For-Sale, Gross Unrealized Losses	(1,501)	(1,208)
Securities Available-For-Sale, Allowance for Credit Losses
Securities Available-For-Sale, Fair Value	17,346	15,616
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	80,644	79,816
Securities held-to-maturity, Gross Unrealized Gains	2	84
Securities held-to-maturity, Gross Unrealized Losses	(8,834)	(7,283)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	71,812	72,617
Securities Held-To-Maturity, Credit Rating	80,644	79,816
Total investment securities, Amortized Cost	99,358	96,563
Total investment securities, Gross Unrealized Gains	135	161
Total investment securities, Gross Unrealized Losses	(10,335)	(8,491)
Total investment securities, Allowance for Credit Losses
Total investment securities, Fair Value	89,158	88,233
Mortgage-backed securities - residential [Member] \| Obligations of U.S. government agencies [Member]
Securities available-for-sale:
Securities Available-For-Sale, Amortized Cost	93	95
Securities Available-For-Sale, Gross Unrealized Gains
Securities Available-For-Sale, Gross Unrealized Losses	(11)	(6)
Securities Available-For-Sale, Allowance for Credit Losses
Securities Available-For-Sale, Fair Value	82	89
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	7,051	7,209
Securities held-to-maturity, Gross Unrealized Gains
Securities held-to-maturity, Gross Unrealized Losses	(817)	(611)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	6,234	6,598
Securities Held-To-Maturity, Credit Rating	7,051	7,209
Mortgage-backed securities - residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Securities available-for-sale:
Securities Available-For-Sale, Amortized Cost	14,621	12,652
Securities Available-For-Sale, Gross Unrealized Gains	34	56
Securities Available-For-Sale, Gross Unrealized Losses	(1,490)	(1,202)
Securities Available-For-Sale, Allowance for Credit Losses
Securities Available-For-Sale, Fair Value	13,165	11,506
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	43,780	42,701
Securities held-to-maturity, Gross Unrealized Gains	2	4
Securities held-to-maturity, Gross Unrealized Losses	(6,527)	(5,194)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	37,255	37,511
Securities Held-To-Maturity, Credit Rating	43,780	42,701
Corporate securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Securities available-for-sale:
Securities Available-For-Sale, Amortized Cost	4,000	4,000
Securities Available-For-Sale, Gross Unrealized Gains	99	21
Securities Available-For-Sale, Gross Unrealized Losses
Securities Available-For-Sale, Allowance for Credit Losses
Securities Available-For-Sale, Fair Value	4,099	4,021
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	3,000	3,000
Securities held-to-maturity, Gross Unrealized Gains
Securities held-to-maturity, Gross Unrealized Losses	(140)	(234)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	2,860	2,766
Securities Held-To-Maturity, Credit Rating	3,000	3,000
Mortgage-backed securities - commercial [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	4,182	4,268
Securities held-to-maturity, Gross Unrealized Gains		64
Securities held-to-maturity, Gross Unrealized Losses	(42)	(23)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	4,140	4,309
Securities Held-To-Maturity, Credit Rating	4,182	4,268
Debt Securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	19,000	19,000
Securities held-to-maturity, Gross Unrealized Gains		13
Securities held-to-maturity, Gross Unrealized Losses	(873)	(865)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	18,127	18,148
Securities Held-To-Maturity, Credit Rating	19,000	19,000
Private label mortgage-backed securities residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	187	190
Securities held-to-maturity, Gross Unrealized Gains
Securities held-to-maturity, Gross Unrealized Losses	(7)	(5)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	180	185
Securities Held-To-Maturity, Credit Rating	187	190
Obligations of state and political subdivisions [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	3,444	3,448
Securities held-to-maturity, Gross Unrealized Gains		3
Securities held-to-maturity, Gross Unrealized Losses	(428)	(351)
Securities held-to-maturity, Allowance for Credit Losses
Securities held-to-maturity, Fair Value	3,016	3,100
Securities Held-To-Maturity, Credit Rating	3,444	3,448
Standard & Poor's, AAA/AA/A Rating [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	80,644	79,816
Securities Held-To-Maturity, Credit Rating	80,644	79,816
Standard & Poor's, AAA/AA/A Rating [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	7,051	7,209
Securities Held-To-Maturity, Credit Rating	7,051	7,209
Standard & Poor's, AAA/AA/A Rating [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	43,780	42,701
Securities Held-To-Maturity, Credit Rating	43,780	42,701
Standard & Poor's, AAA/AA/A Rating [Member] \| Corporate securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	3,000	3,000
Securities Held-To-Maturity, Credit Rating	3,000	3,000
Standard & Poor's, AAA/AA/A Rating [Member] \| Mortgage-backed securities - commercial [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	4,182	4,268
Securities Held-To-Maturity, Credit Rating	4,182	4,268
Standard & Poor's, AAA/AA/A Rating [Member] \| Debt Securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	19,000	19,000
Securities Held-To-Maturity, Credit Rating	19,000	19,000
Standard & Poor's, AAA/AA/A Rating [Member] \| Private label mortgage-backed securities residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	187	190
Securities Held-To-Maturity, Credit Rating	187	190
Standard & Poor's, AAA/AA/A Rating [Member] \| Obligations of state and political subdivisions [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost	3,444	3,448
Securities Held-To-Maturity, Credit Rating	3,444	3,448
Standard & Poor's, BBB/BB/B Rating [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Corporate securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Mortgage-backed securities - commercial [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Debt Securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Private label mortgage-backed securities residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Standard & Poor's, BBB/BB/B Rating [Member] \| Obligations of state and political subdivisions [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Mortgage-backed securities - residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Corporate securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Mortgage-backed securities - commercial [Member] \| Obligations of U.S. government agencies [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Debt Securities [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Private label mortgage-backed securities residential [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating
Non-rated [Member] \| Obligations of state and political subdivisions [Member] \| Obligations of U.S. government-sponsored enterprises [Member]
Obligations of U.S. government agencies:
Securities held-to-maturity, Amortized Cost
Securities Held-To-Maturity, Credit Rating

Gross unrealized losses.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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