LOANS RECEIVABLE, NET AND RELATED ALLOWANCE FOR CREDIT LOSSES - Schedule of Loan Portfolio (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Mar. 31, 2026	Sep. 30, 2025
One-to-four family residential [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	$ 12,972	$ 18,873
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	18,514	32,165
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	31,387	36,663
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	24,585	28,555
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	28,035	23,556
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	118,941	102,642
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	234,434	242,454
One-to-four family residential [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
One-to-four family residential [Member] \| Performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	12,972	18,873
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	18,514	31,952
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	31,387	36,663
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	24,372	28,465
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	28,035	23,556
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	118,941	102,642
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	234,221	242,151
One-to-four family residential [Member] \| Non-performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	213	90
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	213	303
Commercial Real Estate [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	36,485	111,456
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	107,580	86,068
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	85,673	70,546
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	69,159	63,996
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	62,676	54,060
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	187,481	140,977
Revolving Loans Amortized Cost Basis	8,073	6,110
Revolving Loans Converted to Term
Total	557,764	533,213
Commercial Real Estate [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Construction and Land [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	7,635	10,037
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	12,961	12,982
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	12,252	3,405
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	2,166	2,863
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	35,714	29,287
Construction and Land [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Home equity loans and lines of credit [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	196	492
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	452	1,181
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	1,052	1,419
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	770	1,523
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	1,484	265
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,246	1,090
Revolving Loans Amortized Cost Basis	25,110	25,808
Revolving Loans Converted to Term
Total	30,310	31,778
Home equity loans and lines of credit [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Home equity loans and lines of credit [Member] \| Performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	196	492
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	452	1,181
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	1,052	1,271
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	689	1,523
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	1,484	265
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,246	1,090
Revolving Loans Amortized Cost Basis	25,110	25,808
Revolving Loans Converted to Term
Total	30,229	31,630
Home equity loans and lines of credit [Member] \| Non-performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023		148
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	81	148
Commercial Business [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	1,200
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	484	1,195
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	1,053	465
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	441	2,001
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	1,897	1,061
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	2,986	2,270
Revolving Loans Amortized Cost Basis	11,678	12,240
Revolving Loans Converted to Term	139	147
Total	19,878	20,048
Commercial Business [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Other [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	200	464
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	2	18
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,416	1,423
Revolving Loans Amortized Cost Basis	192
Revolving Loans Converted to Term
Total	1,842	2,119
Other [Member] \| Revolving Credit Facility [Member]
One-to-four family residential
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Current period gross charge-offs
Other [Member] \| Performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	200	464
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	2	18
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,416	1,423
Revolving Loans Amortized Cost Basis	192
Revolving Loans Converted to Term
Total	1,842	2,119
Other [Member] \| Non-performing [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Pass [Member] \| Commercial Real Estate [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	36,485	111,456
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	107,580	86,068
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	85,438	70,546
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	68,105	63,905
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	62,586	54,060
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	185,929	140,866
Revolving Loans Amortized Cost Basis	8,073	6,110
Revolving Loans Converted to Term
Total	554,833	533,011
Pass [Member] \| Construction and Land [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	7,635	10,037
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	12,961	12,982
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	12,252	3,405
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,046	2,863
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	34,594	29,287
Pass [Member] \| Commercial Business [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025	1,200
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024	484	1,195
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023	1,053	465
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	441	2,001
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021	1,897	1,061
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	2,986	2,270
Revolving Loans Amortized Cost Basis	11,678	12,240
Revolving Loans Converted to Term	139	147
Total	19,878	20,048
Special Mention [Member] \| Commercial Real Estate [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022	1,054
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior	1,552	111
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total	2,841	202
Special Mention [Member] \| Construction and Land [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Special Mention [Member] \| Commercial Business [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Substandard [Member] \| Commercial Real Estate [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Substandard [Member] \| Construction and Land [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Substandard [Member] \| Commercial Business [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Doubtful [Member] \| Commercial Real Estate [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Doubtful [Member] \| Construction and Land [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total
Doubtful [Member] \| Commercial Business [Member]
One-to-four family residential
Term Loans Amortized Cost Basis by Origination Fiscal Year 2026/ 2025
Term Loans Amortized Cost Basis by Origination Fiscal Year 2025/ 2024
Term Loans Amortized Cost Basis by Origination Fiscal Year 2024/ 2023
Term Loans Amortized Cost Basis by Origination Fiscal Year 2023/ 2022
Term Loans Amortized Cost Basis by Origination Fiscal Year 2022/ 2021
Term Loans Amortized Cost Basis by Origination Fiscal Year Prior
Revolving Loans Amortized Cost Basis
Revolving Loans Converted to Term
Total

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amortized cost of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost of financing receivable originated in current fiscal year. Excludes net investment in lease.

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Amortized cost of financing receivable originated in fiscal year prior to current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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