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INVESTMENT SECURITIES - Equity and other securities (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Equity and other securities |  |
Amortized cost | $ 82,424 | $ 43,917
Gross unrealized gains | 918 | 962
Gross unrealized losses | 0 | 0
Estimated Fair Value | 83,342 | 44,879
Equity securities, at fair value |  |
Amortized cost | 251 | 251
Gross unrealized gains | 168 | 212
Gross unrealized losses | 0 | 0
Estimated Fair Value | 419 | 463
Held-to-Maturity Portfolio: |  |
Amortized Cost | 1,079,695 | 0
Unrealized Gains | 0 | 0
Unrealized Losses | 44,900 | 0
Held-to-maturity securities | 1,034,795 | 0
Federal home loan bank common stock |  |
Other equity securities, at adjusted cost |  |
Amortized cost | 47,497 | 7,188
Gross unrealized gains | 0 | 0
Gross unrealized losses | 0 | 0
Estimated Fair Value | 47,497 | 7,188
Federal reserve bank common stock |  |
Other equity securities, at adjusted cost |  |
Amortized cost | 31,144 | 33,916
Gross unrealized gains | 0 | 0
Gross unrealized losses | 0 | 0
Estimated Fair Value | 31,144 | 33,916
Other equity securities |  |
Other equity securities, at adjusted cost |  |
Amortized cost | 3,532 | 2,562
Gross unrealized gains | 750 | 750
Gross unrealized losses | 0 | 0
Estimated Fair Value | 4,282 | 3,312
U.S. Treasury and agency securities |  |
Equity and other securities |  |
Securities transferred from available-for-sale to held-to-maturity | 1,080,000 |
Pretax unrealized losses related to transfer | 341,200 |
Other equity securities, at adjusted cost |  |
Gross unrealized losses | 417,009 | 106,057
Held-to-Maturity Portfolio: |  |
Amortized Cost | 1,079,695 | 0
Unrealized Gains | 0 | 0
Unrealized Losses | 44,900 | 0
Held-to-maturity securities | $ 1,034,795 | $ 0

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