FAIR VALUE - Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Financial Assets [Abstract]
Available for sale, at fair value	$ 6,740	$ 7,747
Mortgage servicing rights	4,120	3,690
U.S. GSE residential mortgage-backed securities
Financial Assets [Abstract]
Available for sale, at fair value	319	833
Corporate Bonds
Financial Assets [Abstract]
Available for sale, at fair value	6,421	6,914
Recurring [Member]
Financial Assets [Abstract]
Total	10,860	11,437
Recurring [Member] | U.S. GSE residential mortgage-backed securities
Financial Assets [Abstract]
Available for sale, at fair value	319	833
Recurring [Member] | Corporate Bonds
Financial Assets [Abstract]
Available for sale, at fair value	6,421	6,914
Recurring [Member] | Mortgage Servicing Rights [Member]
Financial Assets [Abstract]
Mortgage servicing rights	4,120	3,690
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets [Abstract]
Total	0	0
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | U.S. GSE residential mortgage-backed securities
Financial Assets [Abstract]
Available for sale, at fair value	0	0
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate Bonds
Financial Assets [Abstract]
Available for sale, at fair value	0	0
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Mortgage Servicing Rights [Member]
Financial Assets [Abstract]
Mortgage servicing rights	0	0
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Assets [Abstract]
Total	6,740	7,747
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. GSE residential mortgage-backed securities
Financial Assets [Abstract]
Available for sale, at fair value	319	833
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds
Financial Assets [Abstract]
Available for sale, at fair value	6,421	6,914
Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Mortgage Servicing Rights [Member]
Financial Assets [Abstract]
Mortgage servicing rights	0	0
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial Assets [Abstract]
Total	4,120	3,690
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | U.S. GSE residential mortgage-backed securities
Financial Assets [Abstract]
Available for sale, at fair value	0	0
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Corporate Bonds
Financial Assets [Abstract]
Available for sale, at fair value	0	0
Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member] | Mortgage Servicing Rights [Member]
Financial Assets [Abstract]
Mortgage servicing rights	$ 4,120	$ 3,690