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FAIR VALUE - Carrying amounts and estimated fair values of other financial instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Financial assets: |  |
Held-to-maturity securities | $ 1,276,676 | $ 1,121,816
Carrying Value |  |
Financial assets: |  |
Net loans | 10,175,507 | 9,637,929
Held-to-maturity securities | 1,319,050 | 1,172,174
Financial liabilities: |  |
Deposits | 13,476,171 | 12,928,121
Overnight borrowings | 0 | 53,000
Securities sold under agreement to repurchase, short-term | 317,448 | 304,595
Other Federal Home Loan Bank borrowings | 622,273 | 407,603
Fair Value |  |
Financial assets: |  |
Net loans | 9,897,287 | 9,293,902
Held-to-maturity securities | 1,276,676 | 1,121,816
Financial liabilities: |  |
Deposits | 13,463,479 | 12,907,605
Overnight borrowings | 0 | 53,000
Securities sold under agreement to repurchase, short-term | 317,448 | 304,595
Other Federal Home Loan Bank borrowings | $ 628,532 | $ 410,385

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