SECURITIES - Investment Securities Available for Sale and Held to Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Available for sale [Abstract]
Amortized cost	$ 7,090	$ 7,422
Gross unrealized gains		326
Gross unrealized losses	(350)	(1)
Fair value	6,740	7,747
Held to maturity [Abstract]
Amortized cost	4,509	8,611
Gross unrealized gains		258
Gross unrealized losses	(200)	(4)
Fair value	4,309	8,865
Investment Securities [Abstract]
Amortized cost	11,599	16,033
Gross unrealized gains		584
Gross unrealized losses	(550)	(5)
Fair value	11,049	16,612
Gross unrealized losses in a continuous loss position for less than twelve months	550	5
Investment securities pledged to secure public deposits	1,800	5,100
U.S. GSE residential mortgage-backed securities
Available for sale [Abstract]
Amortized cost	390	722
Gross unrealized gains		112
Gross unrealized losses	(71)	(1)
Fair value	319	833
Held to maturity [Abstract]
Amortized cost	1,858	2,417
Gross unrealized gains		74
Gross unrealized losses	(117)	0
Fair value	1,741	2,491
U.S. GSE commercial mortgage-backed securities
Held to maturity [Abstract]
Amortized cost	2,651	2,694
Gross unrealized gains		175
Gross unrealized losses	(83)	0
Fair value	2,568	2,869
Corporate Bonds
Available for sale [Abstract]
Amortized cost	6,700	6,700
Gross unrealized gains		214
Gross unrealized losses	(279)	0
Fair value	$ 6,421	6,914
Held to maturity [Abstract]
Amortized cost		3,500
Gross unrealized gains		9
Gross unrealized losses		(4)
Fair value		$ 3,505