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INVESTMENT SECURITIES - Equity and other securities (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Equity and Other Securities |  |
Amortized Cost | $ 62,141 | $ 82,424
Gross Unrealized Gains | 868 | 918
Gross Unrealized Losses | 0 | 0
Equity and other securities | 63,009 | 83,342
Equity Securities, at Fair Value |  |
Amortized Cost | 251 | 251
Gross Unrealized Gains | 118 | 168
Gross Unrealized Losses | 0 | 0
Fair Value | 369 | 419
Held-to-Maturity Portfolio: |  |
Amortized Cost | 1,104,020 |
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 40,576 | 44,900
Fair Value | 1,063,444 | 1,034,795
Federal Home Loan Bank Common Stock |  |
Equity and Other Securities |  |
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Equity and other securities | 23,663 | 47,497
Other Equity Securities, at Adjusted Cost |  |
Amortized Cost | 23,663 | 47,497
Federal Reserve Bank Common Stock |  |
Equity and Other Securities |  |
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Equity and other securities | 33,568 | 31,144
Other Equity Securities, at Adjusted Cost |  |
Amortized Cost | 33,568 | 31,144
Other Equity Securities |  |
Equity and Other Securities |  |
Gross Unrealized Gains | 750 | 750
Gross Unrealized Losses | 0 | 0
Equity and other securities | 5,409 | 4,282
Other Equity Securities, at Adjusted Cost |  |
Amortized Cost | 4,659 | 3,532
U.S. Treasury and agency securities |  |
Held-to-Maturity Portfolio: |  |
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 40,454 | 44,900
Fair Value | $ 1,053,813 | $ 1,034,795

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