Fair Value of Financial Instruments - Schedule of Assets Measured At Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Assets:
Securities available for sale, Fair value	$ 725,777
Mortgage-backed securities available for sale	800,309	$ 1,051,041
Securities available for sale	1,526,086	1,676,864
Interest rate contracts	34,007	1,832
Total assets	1,560,093	1,678,696
Liabilities:
Interest rate contracts	0	673
Total liabilities		673
Debt Securities [Member]
Assets:
Securities available for sale, Fair value	725,777	625,823
Debt Securities [Member] \| Obligations of State and Political Subdivisions [Member]
Assets:
Securities available for sale, Fair value	31,078	34,603
Debt Securities [Member] \| Asset-backed Securities [Member]
Assets:
Securities available for sale, Fair value	229,584	242,989
Debt Securities [Member] \| Collateralized Loan Obligations [Member]
Assets:
Securities available for sale, Fair value	311,620	189,880
Debt Securities [Member] \| Corporate Bonds [Member]
Assets:
Securities available for sale, Fair value	153,495	158,351
Collateralized Mortgage Obligations Excluding Pass Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	7,996	13,739
Residential Pass-Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	570,150	744,491
Commercial Pass-Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	222,163	292,811
Significant Other Observable Inputs (Level 2) [Member]
Assets:
Mortgage-backed securities available for sale	800,309	1,051,041
Securities available for sale	1,526,086	1,676,864
Total assets	1,560,093	1,678,696
Liabilities:
Total liabilities		673
Significant Other Observable Inputs (Level 2) [Member] \| Debt Securities [Member]
Assets:
Securities available for sale, Fair value	725,777	625,823
Significant Other Observable Inputs (Level 2) [Member] \| Debt Securities [Member] \| Obligations of State and Political Subdivisions [Member]
Assets:
Securities available for sale, Fair value	31,078	34,603
Significant Other Observable Inputs (Level 2) [Member] \| Debt Securities [Member] \| Asset-backed Securities [Member]
Assets:
Securities available for sale, Fair value	229,584	242,989
Significant Other Observable Inputs (Level 2) [Member] \| Debt Securities [Member] \| Collateralized Loan Obligations [Member]
Assets:
Securities available for sale, Fair value	311,620	189,880
Significant Other Observable Inputs (Level 2) [Member] \| Debt Securities [Member] \| Corporate Bonds [Member]
Assets:
Securities available for sale, Fair value	153,495	158,351
Significant Other Observable Inputs (Level 2) [Member] \| Collateralized Mortgage Obligations Excluding Pass Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	7,996	13,739
Significant Other Observable Inputs (Level 2) [Member] \| Residential Pass-Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	570,150	744,491
Significant Other Observable Inputs (Level 2) [Member] \| Commercial Pass-Through Securities [Member]
Assets:
Mortgage-backed securities available for sale	222,163	292,811
Interest Rate Contract [Member]
Assets:
Interest rate contracts	34,007	1,832
Liabilities:
Interest rate contracts	0	673
Interest Rate Contract [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets:
Interest rate contracts	$ 34,007	1,832
Liabilities:
Interest rate contracts		$ 673

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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 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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