SECURITIES - Schedule of Available for Sale Securities Pledged (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Jun. 30, 2025
Schedule of Available for Sale Securities [Line Items]
Investment securities available for sale	$ 1,000,397	$ 1,012,969
Asset Pledged as Collateral
Schedule of Available for Sale Securities [Line Items]
Investment securities available for sale	146,784	542,045
Asset Pledged as Collateral \| Pledged to secure public funds on deposit
Schedule of Available for Sale Securities [Line Items]
Investment securities available for sale	146,784	475,234
Asset Pledged as Collateral \| Pledged for potential borrowings at the Federal Reserve Bank of New York
Schedule of Available for Sale Securities [Line Items]
Investment securities available for sale	$ 0	$ 66,811

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Kearny Financial Corp. 10-Q