Securities (Details) $ in Thousands	12 Months Ended
Jun. 30, 2018 USD ($) Category	Jun. 30, 2017 USD ($)
Securities [Abstract]
Number of categories utilized under risk management approach of diversified investing \| Category	3
Available-for-sale debt securities [Abstract]
Amortized cost	$ 120,947	$ 90,429
Gross unrealized gains	299	962
Gross unrealized losses	440	92
Estimated fair value	120,806	91,299
Available-for-sale equity securities [Abstract]
Amortized cost	62	62
Gross unrealized gains	155	122
Gross unrealized losses	0	0
Estimated fair value	217	184
Available-for-sale securities [Abstract]
Amortized cost	121,009	90,491
Gross unrealized gains	454	1,084
Gross unrealized losses	440	92
Estimated fair value	121,023	91,483
Held-to-maturity securities [Abstract]
Amortized cost	274,550	223,830
Gross unrealized gains	3,313	4,988
Gross unrealized losses	3,686	366
Estimated fair value	274,177	228,452
Total Securities [Abstract]
Amortized cost	395,559	314,321
Gross unrealized gains	3,767	6,072
Gross unrealized losses	4,126	458
Estimated fair value	395,200	319,935
U.S. Government Sponsored Enterprises [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	5,543	4,566
Gross unrealized gains	18	151
Gross unrealized losses	30	0
Estimated fair value	5,531	4,717
Held-to-maturity securities [Abstract]
Amortized cost	9,245	6,000
Gross unrealized gains	0	0
Gross unrealized losses	278	53
Estimated fair value	8,967	5,947
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	92,052	57,885
Gross unrealized gains	204	227
Gross unrealized losses	1	0
Estimated fair value	92,255	58,112
Held-to-maturity securities [Abstract]
Amortized cost	136,335	115,805
Gross unrealized gains	3,091	3,434
Gross unrealized losses	532	95
Estimated fair value	138,894	119,144
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	3,332	4,868
Gross unrealized gains	13	72
Gross unrealized losses	98	27
Estimated fair value	3,247	4,913
Held-to-maturity securities [Abstract]
Amortized cost	6,472	10,798
Gross unrealized gains	72	274
Gross unrealized losses	7	2
Estimated fair value	6,537	11,070
Mortgage-backed Securities-Multi-Family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	18,249	20,344
Gross unrealized gains	64	483
Gross unrealized losses	244	62
Estimated fair value	18,069	20,765
Held-to-maturity securities [Abstract]
Amortized cost	118,780	88,702
Gross unrealized gains	123	1,259
Gross unrealized losses	2,845	199
Estimated fair value	116,058	89,762
Asset-Backed Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost		1
Gross unrealized gains		0
Gross unrealized losses		0
Estimated fair value		1
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	1,771	2,765
Gross unrealized gains	0	29
Gross unrealized losses	67	3
Estimated fair value	1,704	2,791
Held-to-maturity securities [Abstract]
Amortized cost	1,466	1,000
Gross unrealized gains	11	0
Gross unrealized losses	9	5
Estimated fair value	1,468	995
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	2,252	1,525
Gross unrealized gains	16	21
Gross unrealized losses	15	12
Estimated fair value	$ 2,253	$ 1,534

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