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FAIR VALUE - Carrying amounts and estimated fair values of other financial instruments (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financial assets: |  |
Held-to-maturity securities | $ 1,306,388 | $ 1,220,168
Carrying Value |  |
Financial assets: |  |
Net loans | 10,338,301 | 10,353,251
Held-to-maturity securities | 1,393,837 | 1,345,155
Financial liabilities: |  |
Deposits | 13,892,047 | 13,441,707
Overnight borrowings | 0 | 118,000
Securities sold under agreement to repurchase, short-term | 266,581 | 261,553
Other Federal Home Loan Bank borrowings | 586,876 | 610,646
Fair Value |  |
Financial assets: |  |
Net loans | 10,064,531 | 9,969,696
Held-to-maturity securities | 1,306,388 | 1,220,168
Financial liabilities: |  |
Deposits | 13,862,818 | 13,428,682
Overnight borrowings | 0 | 118,000
Securities sold under agreement to repurchase, short-term | 266,581 | 261,553
Other Federal Home Loan Bank borrowings | $ 601,778 | $ 620,045

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