Securities (Details) $ in Thousands	9 Months Ended
Mar. 31, 2020 USD ($) Category	Jun. 30, 2019 USD ($)
Available-for-sale debt securities [Abstract]
Amortized cost	$ 207,947	$ 121,602
Gross unrealized gains	1,372	1,146
Gross unrealized losses	197	20
Estimated fair value	209,122	122,728
Held-to-maturity securities [Abstract]
Amortized cost	382,532	304,208
Gross unrealized gains	17,042	9,484
Gross unrealized losses	318	79
Estimated fair value	399,256	313,613
Total Securities [Abstract]
Amortized cost	590,479	425,810
Gross unrealized gains	18,414	10,630
Gross unrealized losses	515	99
Estimated fair value	$ 608,378	436,341
Number of categories utilized under risk management approach of diversified investing \| Category	3
U.S. Government Sponsored Enterprises [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	$ 2,506	5,522
Gross unrealized gains	16	31
Gross unrealized losses	0	0
Estimated fair value	2,522	5,553
Held-to-maturity securities [Abstract]
Amortized cost	2,000	9,249
Gross unrealized gains	12	1
Gross unrealized losses	0	14
Estimated fair value	2,012	9,236
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	167,823	95,782
Gross unrealized gains	257	788
Gross unrealized losses	65	0
Estimated fair value	168,015	96,570
Held-to-maturity securities [Abstract]
Amortized cost	191,244	152,358
Gross unrealized gains	8,445	6,212
Gross unrealized losses	274	23
Estimated fair value	199,415	158,547
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	9,814	2,634
Gross unrealized gains	313	31
Gross unrealized losses	0	20
Estimated fair value	10,127	2,645
Held-to-maturity securities [Abstract]
Amortized cost	41,525	4,570
Gross unrealized gains	897	97
Gross unrealized losses	0	0
Estimated fair value	42,422	4,667
Mortgage-backed Securities-Multi-family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	23,293	16,151
Gross unrealized gains	706	259
Gross unrealized losses	1	0
Estimated fair value	23,998	16,410
Held-to-maturity securities [Abstract]
Amortized cost	140,738	134,970
Gross unrealized gains	7,640	3,122
Gross unrealized losses	8	17
Estimated fair value	148,370	138,075
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	4,511	1,513
Gross unrealized gains	80	37
Gross unrealized losses	131	0
Estimated fair value	4,460	1,550
Held-to-maturity securities [Abstract]
Amortized cost	1,993	1,478
Gross unrealized gains	8	18
Gross unrealized losses	36	25
Estimated fair value	1,965	1,471
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	5,032	1,583
Gross unrealized gains	40	34
Gross unrealized losses	0	0
Estimated fair value	$ 5,072	$ 1,617

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