SECURITIES - Securities Available for Sale (Details) - USD ($)	Mar. 31, 2024	Jun. 30, 2023
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	$ 1,232,173,000	$ 1,383,867,000
Gross Unrealized Gains	2,223,000	274,000
Gross Unrealized Losses	135,741,000	156,412,000
Allowance for Credit Losses	0	0
Fair Value	1,098,655,000	1,227,729,000
Debt securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	637,743,000	679,862,000
Gross Unrealized Gains	2,216,000	272,000
Gross Unrealized Losses	21,823,000	31,950,000
Allowance for Credit Losses	0	0
Fair Value	618,136,000	648,184,000
Asset-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	86,707,000	138,281,000
Gross Unrealized Gains	193,000	4,000
Gross Unrealized Losses	540,000	2,115,000
Allowance for Credit Losses	0	0
Fair Value	86,360,000	136,170,000
Collateralized loan obligations
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	405,125,000	381,915,000
Gross Unrealized Gains	2,023,000	268,000
Gross Unrealized Losses	453,000	5,187,000
Allowance for Credit Losses	0	0
Fair Value	406,695,000	376,996,000
Corporate bonds
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	145,911,000	159,666,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	20,830,000	24,648,000
Allowance for Credit Losses	0	0
Fair Value	125,081,000	135,018,000
Mortgage-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	594,430,000	704,005,000
Gross Unrealized Gains	7,000	2,000
Gross Unrealized Losses	113,918,000	124,462,000
Allowance for Credit Losses	0	0
Fair Value	480,519,000	579,545,000
Residential pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	437,009,000	539,506,000
Gross Unrealized Gains	7,000	2,000
Gross Unrealized Losses	92,044,000	103,357,000
Allowance for Credit Losses	0	0
Fair Value	344,972,000	436,151,000
Commercial pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	157,421,000	164,499,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	21,874,000	21,105,000
Allowance for Credit Losses	0	0
Fair Value	$ 135,547,000	$ 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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