Loans and Allowance for Credit Losses - Credit Risk Profile of Association's Loan Portfolio Based on Risk Rating Category and Calendar Year of Origination (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Dec. 31, 2024	Jun. 30, 2024
Financing Receivable, Recorded Investment [Line Items]
2024	$ 103,919	$ 43,030
2023	130,688	142,910
2022	158,800	177,235
2021	81,296	85,294
2020	75,872	79,971
Prior Years	104,058	117,949
Total loans	654,633	646,389
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	103,898	43,030
2023	127,052	142,763
2022	158,751	177,183
2021	79,952	84,877
2020	73,943	78,062
Prior Years	100,918	117,237
Total loans	644,514	643,152
Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2023	3,487
2021	1,200	72
Prior Years	2,400
Total loans	7,087	72
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	21
2023	149	147
2022	49	52
2021	144	345
2020	1,929	1,909
Prior Years	740	712
Total loans	3,032	3,165
One- to Four-Family [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	23,928	14,790
2023	38,713	39,216
2022	48,793	51,267
2021	22,428	24,439
2020	14,283	15,455
Prior Years	29,588	32,096
Total loans	177,733	177,263
Current period recoveries Prior Years	1	3
Current period recoveries Total	1	3
One- to Four-Family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	23,928	14,790
2023	38,713	39,202
2022	48,789	51,262
2021	22,362	24,362
2020	14,283	15,455
Prior Years	29,383	31,926
Total loans	177,458	176,997
One- to Four-Family [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	61	72
Total loans	61	72
One- to Four-Family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2023		14
2022	4	5
2021	5	5
Prior Years	205	170
Total loans	214	194
Multi-Family [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	15,031	573
2023	10,806	9,004
2022	44,592	51,279
2021	20,107	20,346
2020	22,390	22,728
Prior Years	16,445	22,101
Total loans	129,371	126,031
Current period charge-offs 2023	(350)
Current period charge-offs Total	(350)
Current period recoveries 2023	200
Current period recoveries Total	200
Multi-Family [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	15,031	573
2023	10,806	9,004
2022	44,592	51,279
2021	20,107	20,346
2020	22,390	22,728
Prior Years	16,216	21,867
Total loans	129,142	125,797
Multi-Family [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Prior Years	229	234
Total loans	229	234
Home Equity Line of Credit [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	2,840	1,629
2023	2,059	2,361
2022	1,524	1,874
2021	1,519	1,806
2020	692	795
Prior Years	1,253	1,394
Total loans	9,887	9,859
Home Equity Line of Credit [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	2,840	1,629
2023	2,059	2,361
2022	1,524	1,874
2021	1,519	1,806
2020	692	795
Prior Years	1,253	1,394
Total loans	9,887	9,859
Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	15,875	9,123
2023	12,055	21,043
2022	3,250	3,250
Prior Years	146	292
Total loans	31,326	33,708
Construction [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	15,875	9,123
2023	12,055	21,043
2022	3,250	3,250
Prior Years	146	292
Total loans	31,326	33,708
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	18,646	4,602
2023	27,152	29,665
2022	51,677	57,530
2021	31,015	27,772
2020	30,397	31,310
Prior Years	46,461	49,138
Total loans	205,348	200,017
Commercial Real Estate [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	18,646	4,602
2023	27,152	29,665
2022	51,677	57,530
2021	30,030	27,622
2020	29,594	30,489
Prior Years	46,209	48,886
Total loans	203,308	198,794
Commercial Real Estate [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	846
Total loans	846
Commercial Real Estate [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2021	139	150
2020	803	821
Prior Years	252	252
Total loans	1,194	1,223
Commercial Business [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	24,556	10,357
2023	38,023	38,986
2022	7,747	10,205
2021	5,716	10,088
2020	7,878	9,289
Prior Years	10,122	12,859
Total loans	94,042	91,784
Current period charge-offs 2023	(50)
Current period charge-offs Total	(50)
Current period recoveries 2023	50
Current period recoveries 2020	59	242
Current period recoveries Total	109	242
Commercial Business [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	24,535	10,357
2023	34,407	38,853
2022	7,702	10,158
2021	5,423	9,898
2020	6,752	8,201
Prior Years	7,668	12,803
Total loans	86,487	90,270
Commercial Business [Member] \| Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
2023	3,487
2021	293
Prior Years	2,400
Total loans	6,180
Commercial Business [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	21
2023	129	133
2022	45	47
2021	0	190
2020	1,126	1,088
Prior Years	54	56
Total loans	1,375	1,514
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	3,043	1,956
2023	1,880	2,635
2022	1,217	1,830
2021	511	843
2020	232	394
Prior Years	43	69
Total loans	6,926	7,727
Current period charge-offs 2024	(41)	(48)
Current period charge-offs 2022	(1)
Current period charge-offs 2021		(1)
Current period charge-offs Total	(42)	(49)
Current period recoveries 2024	13	14
Current period recoveries Total	13	14
Consumer [Member] \| Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
2024	3,043	1,956
2023	1,860	2,635
2022	1,217	1,830
2021	511	843
2020	232	394
Prior Years	43	69
Total loans	6,906	$ 7,727
Consumer [Member] \| Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
2023	20
Total loans	$ 20

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