Securities (Details) $ in Thousands	12 Months Ended
	Jun. 30, 2020 USD ($) Category	Jun. 30, 2019 USD ($)
Securities [Abstract]
Number of categories utilized under risk management approach of diversified investing | Category	3
Available-for-sale debt securities [Abstract]
Amortized cost	$ 224,340	$ 121,602
Gross unrealized gains	2,386	1,146
Gross unrealized losses	17	20
Estimated fair value	226,709	122,728
Held-to-maturity securities [Abstract]
Amortized cost	383,657	304,208
Gross unrealized gains	22,024	9,484
Gross unrealized losses	169	79
Estimated fair value	405,512	313,613
Total Securities [Abstract]
Amortized cost	607,997	425,810
Gross unrealized gains	24,410	10,630
Gross unrealized losses	186	99
Estimated fair value	632,221	436,341
U.S. Government Sponsored Enterprises [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	502	5,522
Gross unrealized gains	2	31
Gross unrealized losses	0	0
Estimated fair value	504	5,553
Held-to-maturity securities [Abstract]
Amortized cost	2,000	9,249
Gross unrealized gains	11	1
Gross unrealized losses	0	14
Estimated fair value	2,011	9,236
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	176,064	95,782
Gross unrealized gains	1,043	788
Gross unrealized losses	0	0
Estimated fair value	177,107	96,570
Held-to-maturity securities [Abstract]
Amortized cost	210,535	152,358
Gross unrealized gains	14,286	6,212
Gross unrealized losses	3	23
Estimated fair value	224,818	158,547
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	15,148	2,634
Gross unrealized gains	380	31
Gross unrealized losses	0	20
Estimated fair value	15,528	2,645
Held-to-maturity securities [Abstract]
Amortized cost	38,884	4,570
Gross unrealized gains	1,002	97
Gross unrealized losses	15	0
Estimated fair value	39,871	4,667
Mortgage-backed Securities-Multi-Family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	28,116	16,151
Gross unrealized gains	798	259
Gross unrealized losses	4	0
Estimated fair value	28,910	16,410
Held-to-maturity securities [Abstract]
Amortized cost	127,582	134,970
Gross unrealized gains	6,680	3,122
Gross unrealized losses	21	17
Estimated fair value	134,241	138,075
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	4,510	1,513
Gross unrealized gains	163	37
Gross unrealized losses	13	0
Estimated fair value	4,660	1,550
Held-to-maturity securities [Abstract]
Amortized cost	2,593	1,478
Gross unrealized gains	7	18
Gross unrealized losses	130	25
Estimated fair value	2,470	1,471
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	2,063	1,583
Gross unrealized gains	38	34
Gross unrealized losses	0	0
Estimated fair value	$ 2,101	$ 1,617