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SECURITIES AND OTHER INVESTMENTS (Narrative) (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
Schedule Of Debt Investments [Line Items] |  |
Available for sale securities past due or non-accrual | $ 0 | $ 0
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss | 340,361,000 | 403,433,000
AFS securities in an unrealized loss, credit related impairment | 0 | 0
Available for sale securities, allowance for credit losses | 0 | 0
HTM securities past due or non accrual | 0 | 0
Restricted equity securities consist of Federal Reserve Bank stock | 141,200,000 | 82,900,000
Federal Home Loan Bank Stock | $ 18,100,000 | $ 20,100,000
Restricted equity securities as a percentage of outstanding borrowings, required by FHLB | 4.75% | 4.75%
Restricted equity securities as a percentage of outstanding borrowings, required by FRB | 6.00% | 6.00%
Held-to-Maturity Securities |  |
Schedule Of Debt Investments [Line Items] |  |
Accrued interest receivable | $ 7,700,000 | $ 8,400,000
Available-for-sale Securities |  |
Schedule Of Debt Investments [Line Items] |  |
Available for sale securities that had been in a continuous loss position for more than 12 months, Number of issues | security | 704 | 726
Accrued interest receivable | $ 14,700,000 | $ 10,100,000
Mortgage-Backed Securities, Issued by Private Enterprises [Member] |  |
Schedule Of Debt Investments [Line Items] |  |
SSFA rating percentage | 20.00% | 20.00%

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