FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023
Assets:
Investment securities available for sale	$ 1,215,633	$ 1,227,729
Interest rate contracts	80,291	71,624
Total assets	1,295,924	1,299,353
Debt securities
Assets:
Investment securities available for sale	678,951	648,184
Obligations of state and political subdivisions
Assets:
Investment securities available for sale		0
Asset-backed securities
Assets:
Investment securities available for sale	130,576	136,170
Collateralized loan obligations
Assets:
Investment securities available for sale	412,697	376,996
Corporate bonds
Assets:
Investment securities available for sale	135,678	135,018
Mortgage-backed securities
Assets:
Investment securities available for sale	536,682	579,545
Collateralized mortgage obligations
Assets:
Investment securities available for sale		0
Residential pass-through securities
Assets:
Investment securities available for sale	400,218	436,151
Commercial pass-through securities
Assets:
Investment securities available for sale	136,464	143,394
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Investment securities available for sale	0	0
Interest rate contracts	0	0
Total assets	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Debt securities
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of state and political subdivisions
Assets:
Investment securities available for sale		0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Asset-backed securities
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized loan obligations
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate bonds
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed securities
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized mortgage obligations
Assets:
Investment securities available for sale		0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Residential pass-through securities
Assets:
Investment securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Commercial pass-through securities
Assets:
Investment securities available for sale	0	0
Significant Other Observable Inputs (Level 2)
Assets:
Investment securities available for sale	1,215,633	1,227,729
Interest rate contracts	80,291	71,624
Total assets	1,295,924	1,299,353
Significant Other Observable Inputs (Level 2) \| Debt securities
Assets:
Investment securities available for sale	678,951	648,184
Significant Other Observable Inputs (Level 2) \| Obligations of state and political subdivisions
Assets:
Investment securities available for sale		0
Significant Other Observable Inputs (Level 2) \| Asset-backed securities
Assets:
Investment securities available for sale	130,576	136,170
Significant Other Observable Inputs (Level 2) \| Collateralized loan obligations
Assets:
Investment securities available for sale	412,697	376,996
Significant Other Observable Inputs (Level 2) \| Corporate bonds
Assets:
Investment securities available for sale	135,678	135,018
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities
Assets:
Investment securities available for sale	536,682	579,545
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations
Assets:
Investment securities available for sale		0
Significant Other Observable Inputs (Level 2) \| Residential pass-through securities
Assets:
Investment securities available for sale	400,218	436,151
Significant Other Observable Inputs (Level 2) \| Commercial pass-through securities
Assets:
Investment securities available for sale	136,464	143,394
Significant Unobservable Inputs (Level 3)
Assets:
Investment securities available for sale	0	0
Interest rate contracts	0	0
Total assets	0	0
Significant Unobservable Inputs (Level 3) \| Debt securities
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Obligations of state and political subdivisions
Assets:
Investment securities available for sale		0
Significant Unobservable Inputs (Level 3) \| Asset-backed securities
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized loan obligations
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Corporate bonds
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized mortgage obligations
Assets:
Investment securities available for sale		0
Significant Unobservable Inputs (Level 3) \| Residential pass-through securities
Assets:
Investment securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Commercial pass-through securities
Assets:
Investment securities available for sale	0	0
Interest Rate Contract
Assets:
Interest rate contracts	80,291	71,624
Interest Rate Contract \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Interest rate contracts	0	0
Interest Rate Contract \| Significant Other Observable Inputs (Level 2)
Assets:
Interest rate contracts	80,291	71,624
Interest Rate Contract \| Significant Unobservable Inputs (Level 3)
Assets:
Interest rate contracts	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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