Securities (Details) $ in Thousands	6 Months Ended
Dec. 31, 2019 USD ($) Category	Jun. 30, 2019 USD ($)
Available-for-sale debt securities [Abstract]
Amortized cost	$ 192,394	$ 121,602
Gross unrealized gains	730	1,146
Gross unrealized losses	125	20
Estimated fair value	192,999	122,728
Held-to-maturity securities [Abstract]
Amortized cost	331,989	304,208
Gross unrealized gains	12,197	9,484
Gross unrealized losses	290	79
Estimated fair value	343,896	313,613
Total Securities [Abstract]
Amortized cost	524,383	425,810
Gross unrealized gains	12,927	10,630
Gross unrealized losses	415	99
Estimated fair value	$ 536,895	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	$ 4,511	5,522
Gross unrealized gains	19	31
Gross unrealized losses	0	0
Estimated fair value	4,530	5,553
Held-to-maturity securities [Abstract]
Amortized cost	2,000	9,249
Gross unrealized gains	0	1
Gross unrealized losses	3	14
Estimated fair value	1,997	9,236
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	147,915	95,782
Gross unrealized gains	417	788
Gross unrealized losses	0	0
Estimated fair value	148,332	96,570
Held-to-maturity securities [Abstract]
Amortized cost	174,165	152,358
Gross unrealized gains	8,883	6,212
Gross unrealized losses	159	23
Estimated fair value	182,889	158,547
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	10,283	2,634
Gross unrealized gains	50	31
Gross unrealized losses	17	20
Estimated fair value	10,316	2,645
Held-to-maturity securities [Abstract]
Amortized cost	11,302	4,570
Gross unrealized gains	153	97
Gross unrealized losses	1	0
Estimated fair value	11,454	4,667
Mortgage-backed Securities-Multi-family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	25,174	16,151
Gross unrealized gains	182	259
Gross unrealized losses	74	0
Estimated fair value	25,282	16,410
Held-to-maturity securities [Abstract]
Amortized cost	137,193	134,970
Gross unrealized gains	3,093	3,122
Gross unrealized losses	119	17
Estimated fair value	140,167	138,075
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	4,511	1,513
Gross unrealized gains	62	37
Gross unrealized losses	34	0
Estimated fair value	4,539	1,550
Held-to-maturity securities [Abstract]
Amortized cost	1,993	1,478
Gross unrealized gains	21	18
Gross unrealized losses	8	25
Estimated fair value	2,006	1,471
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	5,336	1,583
Gross unrealized gains	47	34
Gross unrealized losses	0	0
Estimated fair value	$ 5,383	$ 1,617

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