Securities (Details) $ in Thousands	3 Months Ended
Sep. 30, 2019 USD ($) Category	Jun. 30, 2019 USD ($)
Available-for-sale debt securities [Abstract]
Amortized cost	$ 158,504	$ 121,602
Gross unrealized gains	809	1,146
Gross unrealized losses	50	20
Estimated fair value	159,263	122,728
Held-to-maturity securities [Abstract]
Amortized cost	304,582	304,208
Gross unrealized gains	10,852	9,484
Gross unrealized losses	112	79
Estimated fair value	315,322	313,613
Total Securities [Abstract]
Amortized cost	463,086	425,810
Gross unrealized gains	11,661	10,630
Gross unrealized losses	162	99
Estimated fair value	$ 474,585	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	$ 4,517	5,522
Gross unrealized gains	28	31
Gross unrealized losses	0	0
Estimated fair value	4,545	5,553
Held-to-maturity securities [Abstract]
Amortized cost	2,000	9,249
Gross unrealized gains	0	1
Gross unrealized losses	12	14
Estimated fair value	1,988	9,236
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	120,630	95,782
Gross unrealized gains	346	788
Gross unrealized losses	0	0
Estimated fair value	120,976	96,570
Held-to-maturity securities [Abstract]
Amortized cost	155,729	152,358
Gross unrealized gains	6,383	6,212
Gross unrealized losses	70	23
Estimated fair value	162,042	158,547
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	8,589	2,634
Gross unrealized gains	51	31
Gross unrealized losses	19	20
Estimated fair value	8,621	2,645
Held-to-maturity securities [Abstract]
Amortized cost	10,154	4,570
Gross unrealized gains	164	97
Gross unrealized losses	0	0
Estimated fair value	10,318	4,667
Mortgage-backed Securities-Multi-family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	20,256	16,151
Gross unrealized gains	323	259
Gross unrealized losses	1	0
Estimated fair value	20,578	16,410
Held-to-maturity securities [Abstract]
Amortized cost	132,795	134,970
Gross unrealized gains	4,257	3,122
Gross unrealized losses	2	17
Estimated fair value	137,050	138,075
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	4,512	1,513
Gross unrealized gains	61	37
Gross unrealized losses	30	0
Estimated fair value	4,543	1,550
Held-to-maturity securities [Abstract]
Amortized cost	1,480	1,478
Gross unrealized gains	12	18
Gross unrealized losses	28	25
Estimated fair value	1,464	1,471
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	2,424	1,583
Gross unrealized gains	36	34
Gross unrealized losses	0	0
Estimated fair value	$ 2,460	$ 1,617

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