Investment Securities - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Debt Securities, Available-for-sale [Line Items]
Investments with an unrealized loss position	$ 80,000		$ 80,000		$ 62,000
Unrealized holding losses, 12 months or more	17,000		17,000		17,000
Unrealized Holding Losses Total, Unrealized Losses	81,000		81,000		69,000
Impairment loss			0	$ 0
U.S. government sponsored enterprise MBS
Debt Securities, Available-for-sale [Line Items]
Principal payments from investment securities available for sale	12,400,000	$ 8,100,000	21,800,000	$ 17,400,000
Payments to acquire Mortgage Backed Securities (MBS) categorized as Held-to-maturity	21,500,000		106,400,000
Investments with an unrealized loss position	63,000		63,000		45,000
Unrealized holding losses, 12 months or more	0		0		0
U.S. SBA securities
Debt Securities, Available-for-sale [Line Items]
Investments with an unrealized loss position	17,000		17,000		17,000
Unrealized holding losses, 12 months or more	$ 17,000		$ 17,000		$ 17,000