Premises and Equipment - Calculated amount of right of use assets and lease liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Right of use assets obtained in exchange for lease obligations: Operating Leases	$ 35	$ 22
Consolidated Balance Sheet [Member]
Operating leases right of use asset	2,735		$ 2,770
Operating leases liability	2,735		$ 2,770
Consolidated Statement Of Income [Member]
Operating lease costs classified as occupancy and equipment expense (includes short-term lease costs)	100	72
Supplemental Disclosures Of Cash Flow Information [Member] | Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$ 85	$ 67