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 after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Loans and Allowance for Loan Losses, Major Loan Segments and Classes (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018
Major Loan Segments and Classes [Abstract]
Total gross loans	$ 897,961		$ 798,105
Allowance for loan losses	(15,205)	$ (13,984)	(13,200)	$ (12,846)	$ (12,673)	$ (12,024)
Unearned origination fees and costs, net	979		833
Net loans receivable	883,735		785,738
Residential Real Estate [Member] \| Residential Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	277,891		267,802
Allowance for loan losses	(1,864)	(1,470)	(2,026)	(2,084)	(2,070)	(2,116)
Residential Real Estate [Member] \| Construction and Land [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	9,097		7,462
Allowance for loan losses	(101)	(93)	(87)	(80)	(93)	(114)
Residential Real Estate [Member] \| Multi-family [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	25,370		24,592
Allowance for loan losses	(153)	(147)	(180)	(168)	(180)	(162)
Commercial Real Estate [Member] \| Real Estate [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	374,155		329,668
Allowance for loan losses	(7,963)	(7,510)	(7,110)	(6,346)	(6,182)	(5,979)
Commercial Real Estate [Member] \| Construction [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	70,348		36,361
Allowance for loan losses	(1,822)	(1,467)	(872)	(993)	(876)	(950)
Consumer Loan [Member] \| Home Equity [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	22,179		23,185
Allowance for loan losses	(273)	(270)	(314)	(304)	(322)	(317)
Consumer Loan [Member] \| Consumer Installment [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	5,280		5,481
Allowance for loan losses	(300)	(366)	(250)	(210)	(290)	(224)
Commercial Loans [Member]
Major Loan Segments and Classes [Abstract]
Total gross loans	113,641		103,554
Allowance for loan losses	$ (2,696)	$ (2,661)	$ (2,361)	$ (2,281)	$ (2,381)	$ (2,128)