SECURITIES - Securities Available for Sale (Details) - USD ($)	Sep. 30, 2023	Jun. 30, 2023
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	$ 1,400,273,000	$ 1,383,867,000
Gross Unrealized Gains	1,125,000	274,000
Gross Unrealized Losses	185,765,000	156,412,000
Allowance for Credit Losses	0	0
Fair Value	1,215,633,000	1,227,729,000
Debt securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	706,188,000	679,862,000
Gross Unrealized Gains	1,125,000	272,000
Gross Unrealized Losses	28,362,000	31,950,000
Allowance for Credit Losses	0	0
Fair Value	678,951,000	648,184,000
Asset-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	132,267,000	138,281,000
Gross Unrealized Gains	100,000	4,000
Gross Unrealized Losses	1,791,000	2,115,000
Allowance for Credit Losses	0	0
Fair Value	130,576,000	136,170,000
Collateralized loan obligations
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	414,307,000	381,915,000
Gross Unrealized Gains	1,025,000	268,000
Gross Unrealized Losses	2,635,000	5,187,000
Allowance for Credit Losses	0	0
Fair Value	412,697,000	376,996,000
Corporate bonds
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	159,614,000	159,666,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	23,936,000	24,648,000
Allowance for Credit Losses	0	0
Fair Value	135,678,000	135,018,000
Mortgage-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	694,085,000	704,005,000
Gross Unrealized Gains	0	2,000
Gross Unrealized Losses	157,403,000	124,462,000
Allowance for Credit Losses	0	0
Fair Value	536,682,000	579,545,000
Residential pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	530,179,000	539,506,000
Gross Unrealized Gains	0	2,000
Gross Unrealized Losses	129,961,000	103,357,000
Allowance for Credit Losses	0	0
Fair Value	400,218,000	436,151,000
Commercial pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	163,906,000	164,499,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	27,442,000	21,105,000
Allowance for Credit Losses	0	0
Fair Value	$ 136,464,000	$ 143,394,000

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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