Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	$ 1,805	$ 1,959
Provision (benefit) charged to expense	374	226
Balance, end of period	2,179	2,453
Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		268
Residential Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	37	19
Provision (benefit) charged to expense	(3)	5
Balance, end of period	34	59
Residential Real Estate | Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		35
Construction Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	502	769
Provision (benefit) charged to expense	1,171	166
Balance, end of period	1,673	768
Construction Real Estate | Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		(167)
Commercial Real Estate
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	188	172
Provision (benefit) charged to expense	(18)	32
Balance, end of period	170	299
Commercial Real Estate | Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		95
Consumer loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	218	153
Provision (benefit) charged to expense	(160)	4
Balance, end of period	58	354
Consumer loans | Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		197
Commercial loans
Allowance for off-balance sheet credit exposure:
Balance, beginning of period	860	846
Provision (benefit) charged to expense	(616)	19
Balance, end of period	$ 244	973
Commercial loans | Impact of adoption ASU 2016-13
Allowance for off-balance sheet credit exposure:
Balance, beginning of period		$ 108