Securities, Components of Securities (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2021 USD ($) Category	Jun. 30, 2021 USD ($)
Available-for-sale debt securities [Abstract]
Amortized cost	$ 404,660	$ 390,415
Gross unrealized gains	809	1,879
Gross unrealized losses	3,845	1,404
Estimated fair value	401,624	390,890
Held-to-maturity securities [Abstract]
Amortized cost	666,294	496,914
Gross unrealized gains	20,205	22,600
Gross unrealized losses	2,244	472
Estimated fair value	684,255	519,042
Total Securities [Abstract]
Amortized cost	1,070,954	887,329
Gross unrealized gains	21,014	24,479
Gross unrealized losses	6,089	1,876
Estimated fair value	$ 1,085,879	909,932
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	$ 13,073	13,079
Gross unrealized gains	5	36
Gross unrealized losses	308	212
Estimated fair value	12,770	12,903
U.S. Treasury Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	19,621	19,672
Gross unrealized gains	21	165
Gross unrealized losses	109	1
Estimated fair value	19,533	19,836
Held-to-maturity securities [Abstract]
Amortized cost	10,943	10,938
Gross unrealized gains	0	28
Gross unrealized losses	117	2
Estimated fair value	10,826	10,964
State and Political Subdivisions [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	219,758	200,436
Gross unrealized gains	91	220
Gross unrealized losses	6	0
Estimated fair value	219,843	200,656
Held-to-maturity securities [Abstract]
Amortized cost	446,852	341,364
Gross unrealized gains	16,330	17,184
Gross unrealized losses	644	303
Estimated fair value	462,538	358,245
Mortgage-backed Securities-Residential [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	33,432	34,861
Gross unrealized gains	189	287
Gross unrealized losses	214	167
Estimated fair value	33,407	34,981
Held-to-maturity securities [Abstract]
Amortized cost	22,945	28,450
Gross unrealized gains	442	584
Gross unrealized losses	97	90
Estimated fair value	23,290	28,944
Mortgage-backed Securities-Multi-family [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	115,769	119,359
Gross unrealized gains	420	1,042
Gross unrealized losses	3,203	994
Estimated fair value	112,986	119,407
Held-to-maturity securities [Abstract]
Amortized cost	169,615	100,330
Gross unrealized gains	3,276	4,635
Gross unrealized losses	1,323	12
Estimated fair value	171,568	104,953
Corporate Debt Securities [Member]
Available-for-sale debt securities [Abstract]
Amortized cost	3,007	3,008
Gross unrealized gains	83	129
Gross unrealized losses	5	30
Estimated fair value	3,085	3,107
Held-to-maturity securities [Abstract]
Amortized cost	15,884	9,892
Gross unrealized gains	157	111
Gross unrealized losses	63	65
Estimated fair value	15,978	9,938
Other Securities [Member]
Held-to-maturity securities [Abstract]
Amortized cost	55	5,940
Gross unrealized gains	0	58
Gross unrealized losses	0	0
Estimated fair value	$ 55	$ 5,998