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FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Carrying Amounts and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Jun. 30, 2023
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investment securities available for sale | $ 1,144,175 | $ 1,227,729
Investment securities held to maturity (fair value of $127,877 and $131,169, respectively) | 141,959 | 146,465
Fair Value | 127,877 | 131,169
Loans held-for-sale | 14,030 | 9,591
Net loans receivable | 5,700,762 | 5,780,687
Accrued interest receivable | 30,258 | 28,133
Fair Value | 44,120 | 71,624
Fair Value | 3,448 | 0
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 73,860 | 70,515
Investment securities available for sale | 0 | 0
Fair Value | 0 | 0
Loans held-for-sale | 0 | 0
Net loans receivable | 0 | 0
FHLB Stock | 0 | 0
Accrued interest receivable | 18 | 14
Fair Value | 0 | 0
Borrowings | 0 | 0
Interest payable on deposits | 3,134 | 1,933
Interest payable on borrowings | 0 | 0
Fair Value | 0 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Deposits other than certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 3,577,574 | 3,611,632
Quoted Prices in Active Markets for Identical Assets (Level 1) | Certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 0 | 0
Significant Other Observable Inputs (Level 2) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 0 | 0
Investment securities available for sale | 1,144,175 | 1,227,729
Fair Value | 127,877 | 131,169
Loans held-for-sale | 14,117 | 9,442
Net loans receivable | 0 | 0
FHLB Stock | 0 | 0
Accrued interest receivable | 9,729 | 8,924
Fair Value | 44,120 | 71,624
Borrowings | 0 | 0
Interest payable on deposits | 0 | 0
Interest payable on borrowings | 0 | 0
Fair Value | 3,448 |
Significant Other Observable Inputs (Level 2) | Deposits other than certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 0 | 0
Significant Other Observable Inputs (Level 2) | Certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 0 | 0
Significant Unobservable Inputs (Level 3) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value | 0 | 0
Loans held-for-sale | 0 | 0
Net loans receivable | 5,211,713 | 5,261,808
FHLB Stock | 0 | 0
Accrued interest receivable | 20,511 | 19,195
Fair Value | 0 | 0
Borrowings | 1,663,644 |
Interest payable on deposits | 3,043 |
Interest payable on borrowings | 5,637 |
Fair Value | 0 |
Significant Unobservable Inputs (Level 3) | Deposits other than certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 0 | 0
Significant Unobservable Inputs (Level 3) | Certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 1,729,407 | 1,989,434
Carrying Amount |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 73,860 | 70,515
Investment securities available for sale | 1,144,175 | 1,227,729
Investment securities held to maturity (fair value of $127,877 and $131,169, respectively) | 141,959 | 146,465
Loans held-for-sale | 14,030 | 9,591
Net loans receivable | 5,700,762 | 5,780,687
FHLB Stock | 83,372 | 71,734
Accrued interest receivable | 30,258 | 28,133
Fair Value | 44,120 | 71,624
Borrowings | 1,667,055 | 1,506,812
Interest payable on deposits | 6,177 | 6,826
Interest payable on borrowings | 5,637 | 5,282
Fair Value | 3,448 |
Carrying Amount | Deposits other than certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 3,577,574 | 3,611,632
Carrying Amount | Certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 1,742,056 | 2,017,551
Fair Value |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Cash and cash equivalents | 73,860 | 70,515
Investment securities available for sale | 1,144,175 | 1,227,729
Fair Value | 127,877 | 131,169
Loans held-for-sale | 14,117 | 9,442
Net loans receivable | 5,211,713 | 5,261,808
FHLB Stock | 0 | 0
Accrued interest receivable | 30,258 | 28,133
Fair Value | 44,120 | 71,624
Borrowings | 1,663,644 | 1,498,920
Interest payable on deposits | 6,177 | 6,826
Interest payable on borrowings | 5,637 | 5,282
Fair Value | 3,448 |
Fair Value | Deposits other than certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | 3,577,574 | 3,611,632
Fair Value | Certificates of deposits |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Deposits | $ 1,729,407 | 1,989,434
Fair Value | Significant Unobservable Inputs (Level 3) |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Borrowings |  | 1,498,920
Interest payable on deposits |  | 4,893
Interest payable on borrowings |  | $ 5,282

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