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SECURITIES AND OTHER INVESTMENTS (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) security | Dec. 31, 2022 USD ($)
Schedule Of Debt Investments [Line Items] |  |  |
Available for sale securities past due or non-accrual | $ 0 | $ 0 |
Available for sale securities that had been in a continuous loss position for more than 12 months, Number of issues | security | 726 | 757 |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss | $ 403,433,000 | $ 382,167,000 |
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 | 82,900,000 | 67,000,000 |
Federal Home Loan Bank Stock | 20,100,000 | 48,400,000 |
Amortization of Tax Equity Investments | 8,800,000 | 4,800,000 | $ 4,100,000
Tax credits and savings on Tax Equity Investments | 10,300,000 | 5,700,000 | $ 4,900,000
Carrying value of Tax Equity Investments | 88,700,000 | 64,300,000 |
Unfunded commitments related to Tax Equity Investments | $ 55,600,000 | $ 39,500,000 |
Restricted equity securities as a percentage of outstanding borrowings, required by FHLB | 4.75% | 4.25% |
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 | $ 8,400,000 | $ 8,400,000 |
Available-for-sale Securities |  |  |
Schedule Of Debt Investments [Line Items] |  |  |
Accrued interest receivable | $ 10,100,000 | $ 9,500,000 |
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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