Fair Value Measurements - Schedule of financial instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2022	Jun. 30, 2022
Financial assets
Cash and cash equivalents	$ 47,718	$ 86,792
Interest-bearing time deposits	2,018	4,768
Stock in FHLB	13,485	5,893
Stock in Federal Reserve Bank of St. Louis	5,805	5,790
Loans receivable, net	2,939,191	2,686,198
Accrued interest receivable	13,870	11,052
Financial liabilities
Deposits	2,851,013	2,815,075
Advances from FHLB	224,973	37,957
Accrued interest payable	1,172	801
Subordinated debt	23,068	23,055
Unrecognized financial instruments (net of contract amount)
Commitments to originate loans	0
Letters of credit	0
Lines of credit	0
Fair Value, Inputs, Level 1
Financial assets
Cash and cash equivalents	47,718	86,792
Financial liabilities
Deposits	2,193,711	2,176,444
Fair Value, Inputs, Level 2
Financial assets
Interest-bearing time deposits	2,018	4,768
Stock in FHLB	13,485	5,893
Stock in Federal Reserve Bank of St. Louis	5,805	5,790
Accrued interest receivable	13,870	11,052
Financial liabilities
Advances from FHLB	222,447	35,916
Accrued interest payable	1,172	801
Fair Value, Inputs, Level 3
Financial assets
Loans receivable, net	2,888,109	2,655,882
Financial liabilities
Deposits	649,026	637,163
Subordinated debt	$ 21,072	$ 22,070