Securities - Securities Available for Sale (Details) - USD ($)	Jun. 30, 2023	Jun. 30, 2022
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 1,383,867,000	$ 1,462,124,000
Gross Unrealized Gains	274,000	260,000
Gross Unrealized Losses	156,412,000	118,291,000
Allowance for Credit Losses	0	0
Investment securities available for sale	1,227,729,000	1,344,093,000
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	679,862,000	673,555,000
Gross Unrealized Gains	272,000	214,000
Gross Unrealized Losses	31,950,000	17,567,000
Allowance for Credit Losses	0	0
Investment securities available for sale	648,184,000	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
Investment securities available for sale		28,435,000
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	138,281,000	169,506,000
Gross Unrealized Gains	4,000	0
Gross Unrealized Losses	2,115,000	2,949,000
Allowance for Credit Losses	0	0
Investment securities available for sale	136,170,000	166,557,000
Collateralized loan obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	381,915,000	315,693,000
Gross Unrealized Gains	268,000	0
Gross Unrealized Losses	5,187,000	7,880,000
Allowance for Credit Losses	0	0
Investment securities available for sale	376,996,000	307,813,000
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	159,666,000	159,871,000
Gross Unrealized Gains	0	175,000
Gross Unrealized Losses	24,648,000	6,649,000
Allowance for Credit Losses	0	0
Investment securities available for sale	135,018,000	153,397,000
Mortgage-backed securities:
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	704,005,000	788,569,000
Gross Unrealized Gains	2,000	46,000
Gross Unrealized Losses	124,462,000	100,724,000
Allowance for Credit Losses	0	0
Investment securities available for sale	579,545,000	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
Investment securities available for sale		7,122,000
Residential pass-through securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	539,506,000	595,337,000
Gross Unrealized Gains	2,000	45,000
Gross Unrealized Losses	103,357,000	80,624,000
Allowance for Credit Losses	0	0
Investment securities available for sale	436,151,000	514,758,000
Commercial pass-through securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	164,499,000	185,781,000
Gross Unrealized Gains	0	1,000
Gross Unrealized Losses	21,105,000	19,771,000
Allowance for Credit Losses	0	0
Investment securities available for sale	$ 143,394,000	$ 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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