Fair Value of Assets and Liabilities - Level 3 (Details)	3 Months Ended				6 Months Ended
	Dec. 31, 2022 USD ($) security	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2022 USD ($) security	Jun. 30, 2022 security
Fair Value of Assets and Liabilities
Beginning balance	$ 1,840,000	$ 1,900,000	$ 0	$ 0	$ 1,900,000
Transfer of security from Level 2 to Level 3	0		2,000,000
Unrealized gains (losses) included in other comprehensive income (loss)	(240,000)	(60,000)		0
Ending balance	$ 1,600,000	$ 1,840,000	$ 2,000,000	$ 0	$ 1,600,000
Number of investment securities measured at fair value on a recurring basis using significant unobservable inputs | security	1				1	1
Significant unobservable input					The Level 3 valuation is based on the 5/30 swap curve
Significant unobservable input, float	1.00%				1.00%