FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Assets Measured At Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Jun. 30, 2022
Assets:
Fair Value	$ 1,267,066	$ 1,344,093
Interest rate contracts	47,816	41,223
Total assets	1,314,882	1,385,316
Liabilities:
Interest rate contracts	7,847
Total liabilities	7,847
Debt securities:
Assets:
Fair Value	667,444	656,202
Obligations of state and political subdivisions
Assets:
Fair Value		28,435
Asset-backed securities
Assets:
Fair Value	143,053	166,557
Collateralized loan obligations
Assets:
Fair Value	381,937	307,813
Corporate bonds
Assets:
Fair Value	142,454	153,397
Mortgage-backed securities:
Assets:
Fair Value	599,622	687,891
Collateralized mortgage obligations
Assets:
Fair Value		7,122
Residential pass-through securities
Assets:
Fair Value	451,241	514,758
Commercial pass-through securities
Assets:
Fair Value	148,381	166,011
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Fair Value	0	0
Interest rate contracts	0	0
Total assets	0	0
Liabilities:
Interest rate contracts	0
Total liabilities	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Debt securities:
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of state and political subdivisions
Assets:
Fair Value		0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Asset-backed securities
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized loan obligations
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate bonds
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed securities:
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized mortgage obligations
Assets:
Fair Value		0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Residential pass-through securities
Assets:
Fair Value	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Commercial pass-through securities
Assets:
Fair Value	0	0
Significant Other Observable Inputs (Level 2)
Assets:
Fair Value	1,267,066	1,344,093
Interest rate contracts	47,816	41,223
Total assets	1,314,882	1,385,316
Liabilities:
Interest rate contracts	7,847
Total liabilities	7,847
Significant Other Observable Inputs (Level 2) \| Debt securities:
Assets:
Fair Value	667,444	656,202
Significant Other Observable Inputs (Level 2) \| Obligations of state and political subdivisions
Assets:
Fair Value		28,435
Significant Other Observable Inputs (Level 2) \| Asset-backed securities
Assets:
Fair Value	143,053	166,557
Significant Other Observable Inputs (Level 2) \| Collateralized loan obligations
Assets:
Fair Value	381,937	307,813
Significant Other Observable Inputs (Level 2) \| Corporate bonds
Assets:
Fair Value	142,454	153,397
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities:
Assets:
Fair Value	599,622	687,891
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations
Assets:
Fair Value		7,122
Significant Other Observable Inputs (Level 2) \| Residential pass-through securities
Assets:
Fair Value	451,241	514,758
Significant Other Observable Inputs (Level 2) \| Commercial pass-through securities
Assets:
Fair Value	148,381	166,011
Significant Unobservable Inputs (Level 3)
Assets:
Fair Value	0	0
Interest rate contracts	0	0
Total assets	0	0
Liabilities:
Interest rate contracts	0
Total liabilities	0
Significant Unobservable Inputs (Level 3) \| Debt securities:
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Obligations of state and political subdivisions
Assets:
Fair Value		0
Significant Unobservable Inputs (Level 3) \| Asset-backed securities
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized loan obligations
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Corporate bonds
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities:
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized mortgage obligations
Assets:
Fair Value		0
Significant Unobservable Inputs (Level 3) \| Residential pass-through securities
Assets:
Fair Value	0	0
Significant Unobservable Inputs (Level 3) \| Commercial pass-through securities
Assets:
Fair Value	0	0
Interest Rate Contract
Assets:
Interest rate contracts	47,816	41,223
Liabilities:
Interest rate contracts	7,847
Interest Rate Contract \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Interest rate contracts	0	0
Liabilities:
Interest rate contracts	0
Interest Rate Contract \| Significant Other Observable Inputs (Level 2)
Assets:
Interest rate contracts	47,816	41,223
Liabilities:
Interest rate contracts	7,847
Interest Rate Contract \| Significant Unobservable Inputs (Level 3)
Assets:
Interest rate contracts	0	$ 0
Liabilities:
Interest rate contracts	$ 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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