Loans - Allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Allowance for credit losses:
Beginning balance	$ 3,613	$ 3,519
Recoveries	8
(Recovery) provision for loan losses	(30)	66
Ending Balance	3,591	3,585
Allowance ending balance:
Collectively evaluated for impairment	3,591
Allowance for loan losses	3,591	3,585	$ 3,613
Loans receivable ,Individually evaluated for impairment	4,152
Loans receivable, Collectively evaluated for impairment	305,292
Total Loans	458,512		465,629
Acquired credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	162
Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	148,906
Residential real estate \| 1-4 Family
Allowance for credit losses:
Beginning balance	709	682
(Recovery) provision for loan losses	(51)	49
Ending Balance	658	731
Allowance ending balance:
Collectively evaluated for impairment	658		709
Allowance for loan losses	658	731	709
Loans receivable ,Individually evaluated for impairment	1,743		1,907
Loans receivable, Collectively evaluated for impairment	83,773		87,540
Total Loans	162,822		173,306
Residential real estate \| 1-4 Family \| Acquired credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	139		138
Residential real estate \| 1-4 Family \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	77,167		83,721
Residential real estate \| Home equity and HELOCs
Allowance for credit losses:
Beginning balance	133	166
Recoveries	7
(Recovery) provision for loan losses	(17)	(16)
Ending Balance	123	150
Allowance ending balance:
Collectively evaluated for impairment	123		133
Allowance for loan losses	123	150	133
Loans receivable ,Individually evaluated for impairment	499		578
Loans receivable, Collectively evaluated for impairment	13,988		14,617
Total Loans	34,546		37,222
Residential real estate \| Home equity and HELOCs \| Acquired credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	23		23
Residential real estate \| Home equity and HELOCs \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	20,036		22,004
Residential real estate \| Construction Residential
Allowance for credit losses:
Beginning balance	487	526
(Recovery) provision for loan losses	(101)	(65)
Ending Balance	386	461
Allowance ending balance:
Collectively evaluated for impairment	386		487
Allowance for loan losses	386	461	487
Loans receivable, Collectively evaluated for impairment	8,487		8,582
Total Loans	10,734		10,841
Residential real estate \| Construction Residential \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	2,247		2,259
Commercial real estate \| 1 - 4 family investor
Allowance for credit losses:
Beginning balance	843	801
(Recovery) provision for loan losses	33	58
Ending Balance	876	859
Allowance ending balance:
Collectively evaluated for impairment	876		843
Allowance for loan losses	876	859	843
Loans receivable ,Individually evaluated for impairment	554		433
Loans receivable, Collectively evaluated for impairment	99,093		98,043
Total Loans	120,620		120,581
Commercial real estate \| 1 - 4 family investor \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	20,973		22,105
Commercial real estate \| Multi-family (five or more)
Allowance for credit losses:
Beginning balance	159	123
(Recovery) provision for loan losses	(11)	(2)
Ending Balance	148	121
Allowance ending balance:
Collectively evaluated for impairment	148		159
Allowance for loan losses	148	121	159
Loans receivable ,Individually evaluated for impairment	503		176
Loans receivable, Collectively evaluated for impairment	10,781		12,008
Total Loans	11,367		12,315
Commercial real estate \| Multi-family (five or more) \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	83		131
Commercial real estate \| Commercial non-residential
Allowance for credit losses:
Beginning balance	854	727
(Recovery) provision for loan losses	114	53
Ending Balance	968	780
Allowance ending balance:
Collectively evaluated for impairment	968		854
Allowance for loan losses	968	780	854
Loans receivable ,Individually evaluated for impairment	853		892
Loans receivable, Collectively evaluated for impairment	78,746		68,530
Total Loans	104,759		96,612
Commercial real estate \| Commercial non-residential \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	25,160		27,190
Commercial real estate \| Construction and Land
Allowance for credit losses:
Beginning balance	362
Ending Balance	368
Allowance ending balance:
Collectively evaluated for impairment	368		362
Allowance for loan losses	368		362
Loans receivable, Collectively evaluated for impairment	6,474		6,377
Total Loans	6,474		6,377
Commercial
Allowance for credit losses:
Beginning balance	51	83
(Recovery) provision for loan losses	(2)	(51)
Ending Balance	49	32
Allowance ending balance:
Collectively evaluated for impairment	49		51
Allowance for loan losses	49	32	51
Loans receivable, Collectively evaluated for impairment	3,421		4,151
Total Loans	4,515		5,145
Commercial \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	1,094		994
Commercial \| Construction and Land
Allowance for credit losses:
Beginning balance	362	396
(Recovery) provision for loan losses	6	40
Ending Balance	368	436
Allowance ending balance:
Allowance for loan losses	368	436	362
Consumer
Allowance for credit losses:
Beginning balance	15	15
Recoveries	1
(Recovery) provision for loan losses	(1)
Ending Balance	15	15
Allowance ending balance:
Collectively evaluated for impairment	15		15
Allowance for loan losses	15	$ 15	15
Loans receivable, Collectively evaluated for impairment	529		535
Total Loans	2,675		3,230
Consumer \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment	2,146		2,695
Unallocated
Allowance for credit losses:
Beginning balance	$ 3,613
Allowance ending balance:
Collectively evaluated for impairment			3,613
Allowance for loan losses			3,613
Loans receivable ,Individually evaluated for impairment			3,986
Loans receivable, Collectively evaluated for impairment			300,383
Total Loans			465,629
Unallocated \| Acquired credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment			161
Unallocated \| Acquired non-credit impaired
Allowance ending balance:
Loans receivable, Collectively evaluated for impairment			$ 161,099

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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