Securities - Securities Available for Sale (Detail) - USD ($)	Dec. 31, 2022	Jun. 30, 2022
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 1,437,195,000	$ 1,462,124,000
Gross Unrealized Gains	42,000	260,000
Gross Unrealized Losses	150,883,000	118,291,000
Allowance for Credit Losses	0	0
Fair Value	1,286,354,000	1,344,093,000
Debt securities:
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	714,305,000	673,555,000
Gross Unrealized Gains	34,000	214,000
Gross Unrealized Losses	26,702,000	17,567,000
Allowance for Credit Losses	0	0
Fair Value	687,637,000	656,202,000
Obligations of state and political subdivisions
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		28,485,000
Gross Unrealized Gains		39,000
Gross Unrealized Losses		89,000
Allowance for Credit Losses		0
Fair Value		28,435,000
Asset-backed securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	161,509,000	169,506,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	2,886,000	2,949,000
Allowance for Credit Losses	0	0
Fair Value	158,623,000	166,557,000
Collateralized loan obligations
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	393,027,000	315,693,000
Gross Unrealized Gains	31,000	0
Gross Unrealized Losses	8,999,000	7,880,000
Allowance for Credit Losses	0	0
Fair Value	384,059,000	307,813,000
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	159,769,000	159,871,000
Gross Unrealized Gains	3,000	175,000
Gross Unrealized Losses	14,817,000	6,649,000
Allowance for Credit Losses	0	0
Fair Value	144,955,000	153,397,000
Mortgage-backed securities:
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	722,890,000	788,569,000
Gross Unrealized Gains	8,000	46,000
Gross Unrealized Losses	124,181,000	100,724,000
Allowance for Credit Losses	0	0
Fair Value	598,717,000	687,891,000
Collateralized mortgage obligations
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		7,451,000
Gross Unrealized Gains		0
Gross Unrealized Losses		329,000
Allowance for Credit Losses		0
Fair Value		7,122,000
Residential pass-through securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	557,294,000	595,337,000
Gross Unrealized Gains	8,000	45,000
Gross Unrealized Losses	107,146,000	80,624,000
Allowance for Credit Losses	0	0
Fair Value	450,156,000	514,758,000
Commercial pass-through securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	165,596,000	185,781,000
Gross Unrealized Gains	0	1,000
Gross Unrealized Losses	17,035,000	19,771,000
Allowance for Credit Losses	0	0
Fair Value	$ 148,561,000	$ 166,011,000

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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-Section 50
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