Loans and Allowance for Loan Losses, Activity and Allocation of Allowance for Loan Losses (Details) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Jun. 30, 2019
Allowance for Loan Losses [Abstract]
Increase in provision for credit losses to reserve for losses resulting from COVID-19 pandemic	$ 500,000
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	13,984,000	$ 12,673,000	$ 13,200,000	$ 12,024,000
Charge-offs	240,000	220,000	793,000	505,000
Recoveries	36,000	43,000	132,000	269,000
Provision	1,425,000	350,000	2,666,000	1,058,000
Balance, end of period	15,205,000	12,846,000	15,205,000	12,846,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	241,000		241,000		$ 262,000
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	14,964,000		14,964,000		12,938,000
Loans receivable, ending balance, impairment analysis individually evaluated	3,625,000		3,625,000		3,894,000
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 894,336,000		$ 894,336,000		794,211,000
Smaller Commercial Loans [Member] | Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days		90 days
Residential Real Estate [Member] | Residential Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 1,470,000	2,070,000	$ 2,026,000	2,116,000
Charge-offs	0	0	101,000	96,000
Recoveries	3,000	0	13,000	13,000
Provision	391,000	14,000	(74,000)	51,000
Balance, end of period	1,864,000	2,084,000	1,864,000	2,084,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	133,000		133,000		188,000
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,731,000		1,731,000		1,838,000
Loans receivable, ending balance, impairment analysis individually evaluated	2,132,000		2,132,000		2,147,000
Loans receivable, ending balance, impairment analysis collectively evaluated	275,759,000		275,759,000		265,655,000
Residential Real Estate [Member] | Construction and Land [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	93,000	93,000	87,000	114,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	8,000	(13,000)	14,000	(34,000)
Balance, end of period	101,000	80,000	101,000	80,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	101,000		101,000		87,000
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	9,097,000		9,097,000		7,462,000
Residential Real Estate [Member] | Multi-family [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	147,000	180,000	180,000	162,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	6,000	(12,000)	(27,000)	6,000
Balance, end of period	153,000	168,000	153,000	168,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	153,000		153,000		180,000
Loans receivable, ending balance, impairment analysis individually evaluated	127,000		127,000		0
Loans receivable, ending balance, impairment analysis collectively evaluated	25,243,000		25,243,000		24,592,000
Commercial Real Estate [Member] | Real Estate [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	7,510,000	6,182,000	7,110,000	5,979,000
Charge-offs	0	74,000	0	74,000
Recoveries	0	0	0	0
Provision	453,000	238,000	853,000	441,000
Balance, end of period	7,963,000	6,346,000	7,963,000	6,346,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	7,963,000		7,963,000		7,110,000
Loans receivable, ending balance, impairment analysis individually evaluated	351,000		351,000		717,000
Loans receivable, ending balance, impairment analysis collectively evaluated	373,804,000		373,804,000		328,951,000
Commercial Real Estate [Member] | Construction [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	1,467,000	876,000	872,000	950,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	355,000	117,000	950,000	43,000
Balance, end of period	1,822,000	993,000	1,822,000	993,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	13,000		13,000		2,000
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	1,809,000		1,809,000		870,000
Loans receivable, ending balance, impairment analysis individually evaluated	102,000		102,000		102,000
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 70,246,000		$ 70,246,000		36,259,000
Consumer Loan [Member] | Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days		90 days
Consumer Loan [Member] | Home Equity [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	$ 270,000	322,000	$ 314,000	317,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	3,000	(18,000)	(41,000)	(13,000)
Balance, end of period	273,000	304,000	273,000	304,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	73,000		73,000		59,000
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	200,000		200,000		255,000
Loans receivable, ending balance, impairment analysis individually evaluated	585,000		585,000		657,000
Loans receivable, ending balance, impairment analysis collectively evaluated	21,594,000		21,594,000		22,528,000
Consumer Loan [Member] | Consumer Installment [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	366,000	290,000	250,000	224,000
Charge-offs	111,000	95,000	359,000	284,000
Recoveries	33,000	43,000	83,000	103,000
Provision	12,000	(28,000)	326,000	167,000
Balance, end of period	300,000	210,000	300,000	210,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	300,000		300,000		250,000
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	5,280,000		$ 5,280,000		5,481,000
Consumer Loan [Member] | Consumer Installment [Member] | Unsecured [Member]
Allowance for Loan Losses [Abstract]
Threshold period to charge off overdrawn deposit accounts against allowance for loan losses			60 days
Commercial Loans [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	2,661,000	2,381,000	$ 2,361,000	2,128,000
Charge-offs	129,000	51,000	333,000	51,000
Recoveries	0	0	36,000	153,000
Provision	164,000	(49,000)	632,000	51,000
Balance, end of period	2,696,000	2,281,000	2,696,000	2,281,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	22,000		22,000		13,000
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	2,674,000		2,674,000		2,348,000
Loans receivable, ending balance, impairment analysis individually evaluated	328,000		328,000		271,000
Loans receivable, ending balance, impairment analysis collectively evaluated	113,313,000		113,313,000		103,283,000
Unallocated [Member]
Activity of allowance for loan losses by loan category [Roll Forward]
Balance, beginning of period	0	279,000	0	34,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	33,000	101,000	33,000	346,000
Balance, end of period	33,000	$ 380,000	33,000	$ 380,000
Allocation of allowance for loan losses by loan category [Abstract]
Allowance for loan losses, ending balance, impairment analysis individually evaluated	0		0		0
Allowance for loan losses, ending balance, impairment analysis collectively evaluated	33,000		33,000		0
Loans receivable, ending balance, impairment analysis individually evaluated	0		0		0
Loans receivable, ending balance, impairment analysis collectively evaluated	$ 0		$ 0		$ 0