LOANS AND ALLOWANCE FOR CREDIT LOSSES - Risk category of bank loans by year of origination (Details)	3 Months Ended
Jun. 30, 2023 USD ($)
Origination year
2024	$ 8,108,000
2023	158,801,000
2022	350,032,000
2021	137,630,000
2020	88,219,000
Prior	234,996,000
Revolving Loans	26,621,000
Total Loans Receivable	1,004,407,000
Gross write-offs
2023	11,000
Total Loans Receivable	11,000
Commercial Real Estate Portfolio Segment
Origination year
Total Loans Receivable	906,011,000
Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2024	4,314,000
2023	63,419,000
2022	89,900,000
2021	34,254,000
2020	19,417,000
Prior	16,626,000
Revolving Loans	16,795,000
Total Loans Receivable	244,725,000
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
2024	1,564,000
2023	65,785,000
2022	144,067,000
2021	91,666,000
2020	54,754,000
Prior	198,803,000
Total Loans Receivable	556,639,000
Commercial Real Estate Portfolio Segment \| Land
Origination year
2023	2,499,000
2022	1,407,000
2021	1,856,000
2020	119,000
Prior	486,000
Total Loans Receivable	6,367,000
Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2024	398,000
2023	3,474,000
2022	32,575,000
2021	5,474,000
2020	9,359,000
Prior	3,060,000
Total Loans Receivable	54,340,000
Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2024	1,687,000
2023	22,915,000
2022	19,214,000
Revolving Loans	124,000
Total Loans Receivable	43,940,000
Consumer
Origination year
Total Loans Receivable	98,396,000
Gross write-offs
Total Loans Receivable	11,000
Consumer \| Real estate one-to-four family
Origination year
2024	4,000
2022	62,576,000
2021	4,255,000
2020	4,512,000
Prior	15,987,000
Revolving Loans	9,273,000
Total Loans Receivable	96,607,000
Consumer \| Other installment
Origination year
2024	141,000
2023	709,000
2022	293,000
2021	125,000
2020	58,000
Prior	34,000
Revolving Loans	429,000
Total Loans Receivable	1,789,000
Gross write-offs
2023	11,000
Total Loans Receivable	11,000
Pass
Origination year
2024	8,108,000
2023	158,279,000
2022	350,032,000
2021	137,630,000
2020	87,503,000
Prior	214,259,000
Revolving Loans	22,948,000
Total Loans Receivable	978,759,000
Pass \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2024	4,314,000
2023	63,317,000
2022	89,900,000
2021	34,254,000
2020	18,736,000
Prior	16,061,000
Revolving Loans	13,122,000
Total Loans Receivable	239,704,000
Pass \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
2024	1,564,000
2023	65,785,000
2022	144,067,000
2021	91,666,000
2020	54,754,000
Prior	178,736,000
Total Loans Receivable	536,572,000
Pass \| Commercial Real Estate Portfolio Segment \| Land
Origination year
2023	2,402,000
2022	1,407,000
2021	1,856,000
2020	119,000
Prior	486,000
Total Loans Receivable	6,270,000
Pass \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2024	398,000
2023	3,474,000
2022	32,575,000
2021	5,474,000
2020	9,324,000
Prior	2,996,000
Total Loans Receivable	54,241,000
Pass \| Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2024	1,687,000
2023	22,592,000
2022	19,214,000
Revolving Loans	124,000
Total Loans Receivable	43,617,000
Pass \| Consumer \| Real estate one-to-four family
Origination year
2024	4,000
2022	62,576,000
2021	4,255,000
2020	4,512,000
Prior	15,946,000
Revolving Loans	9,273,000
Total Loans Receivable	96,566,000
Pass \| Consumer \| Other installment
Origination year
2024	141,000
2023	709,000
2022	293,000
2021	125,000
2020	58,000
Prior	34,000
Revolving Loans	429,000
Total Loans Receivable	1,789,000
Special Mention
Origination year
2023	522,000
2020	716,000
Prior	19,627,000
Revolving Loans	3,673,000
Total Loans Receivable	24,538,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
2023	102,000
2020	681,000
Prior	455,000
Revolving Loans	3,673,000
Total Loans Receivable	4,911,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
Prior	19,139,000
Total Loans Receivable	19,139,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Land
Origination year
2023	97,000
Total Loans Receivable	97,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
2020	35,000
Prior	33,000
Total Loans Receivable	68,000
Special Mention \| Commercial Real Estate Portfolio Segment \| Real Estate Construction
Origination year
2023	323,000
Total Loans Receivable	323,000
Substandard
Origination year
Prior	1,110,000
Total Loans Receivable	1,110,000
Substandard \| Commercial Real Estate Portfolio Segment \| Commercial Business
Origination year
Prior	110,000
Total Loans Receivable	110,000
Substandard \| Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Origination year
Prior	928,000
Total Loans Receivable	928,000
Substandard \| Commercial Real Estate Portfolio Segment \| Multi-Family
Origination year
Prior	31,000
Total Loans Receivable	31,000
Substandard \| Consumer \| Real estate one-to-four family
Origination year
Prior	41,000
Total Loans Receivable	$ 41,000

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable that can be withdrawn, repaid, and redrawn.

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