SECURITIES - Securities Available for Sale (Details) - USD ($)	Mar. 31, 2025	Jun. 30, 2024
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	$ 1,116,087,000	$ 1,203,506,000
Gross Unrealized Gains	2,230,000	2,920,000
Gross Unrealized Losses	114,924,000	133,593,000
Allowance for Credit Losses	0	0
Fair Value	1,003,393,000	1,072,833,000
Debt securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	532,397,000	618,179,000
Gross Unrealized Gains	1,762,000	2,855,000
Gross Unrealized Losses	10,150,000	19,254,000
Allowance for Credit Losses	0	0
Fair Value	524,009,000	601,780,000
Asset-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	69,962,000	80,305,000
Gross Unrealized Gains	117,000	217,000
Gross Unrealized Losses	476,000	82,000
Allowance for Credit Losses	0	0
Fair Value	69,603,000	80,440,000
Collateralized loan obligations
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	323,466,000	386,983,000
Gross Unrealized Gains	1,378,000	2,574,000
Gross Unrealized Losses	108,000	14,000
Allowance for Credit Losses	0	0
Fair Value	324,736,000	389,543,000
Corporate bonds
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	138,969,000	150,891,000
Gross Unrealized Gains	267,000	64,000
Gross Unrealized Losses	9,566,000	19,158,000
Allowance for Credit Losses	0	0
Fair Value	129,670,000	131,797,000
Mortgage-backed securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	583,690,000	585,327,000
Gross Unrealized Gains	468,000	65,000
Gross Unrealized Losses	104,774,000	114,339,000
Allowance for Credit Losses	0	0
Fair Value	479,384,000	471,053,000
Residential pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	429,942,000	429,473,000
Gross Unrealized Gains	7,000	2,000
Gross Unrealized Losses	84,355,000	92,211,000
Allowance for Credit Losses	0	0
Fair Value	345,594,000	337,264,000
Commercial pass-through securities
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	153,748,000	155,854,000
Gross Unrealized Gains	461,000	63,000
Gross Unrealized Losses	20,419,000	22,128,000
Allowance for Credit Losses	0	0
Fair Value	$ 133,790,000	$ 133,789,000

Kearny Financial Corp. 10-Q