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v3.23.3

INVESTMENT SECURITIES - Available-for-Sale Portfolio (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 | Dec. 31, 2022
Available-for-Sale Portfolio |  |
Amortized Cost | $ 3,314,815 | $ 4,675,474
Gross Unrealized Gains | 26 | 565
Gross Unrealized Losses | 547,205 | 524,188
Fair Value | 2,767,636 | 4,151,851
Held-to-Maturity Portfolio |  |
Amortized Cost | 1,125,540 | 1,079,695
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 134,880 | 44,900
Fair Value | 990,660 | 1,034,795
Equity Securities, at Fair Value |  |
Amortized Cost | 251 | 251
Gross Unrealized Gains | 69 | 168
Gross Unrealized Losses | 0 | 0
Fair Value | 320 | 419
U.S. Treasury and agency securities |  |
Available-for-Sale Portfolio |  |
Amortized Cost | 2,378,607 | 3,660,546
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 399,168 | 417,009
Fair Value | 1,979,439 | 3,243,537
Held-to-Maturity Portfolio |  |
Amortized Cost | 1,101,679 | 1,079,695
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 134,091 | 44,900
Fair Value | 967,588 | 1,034,795
Obligations of state and political subdivisions |  |
Available-for-Sale Portfolio |  |
Amortized Cost | 506,838 | 549,118
Gross Unrealized Gains | 20 | 506
Gross Unrealized Losses | 72,393 | 45,327
Fair Value | 434,465 | 504,297
Government agency mortgage-backed securities |  |
Available-for-Sale Portfolio |  |
Amortized Cost | 411,083 | 444,689
Gross Unrealized Gains | 6 | 58
Gross Unrealized Losses | 74,018 | 60,114
Fair Value | 337,071 | 384,633
Held-to-Maturity Portfolio |  |
Amortized Cost | 23,861 | 0
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 789 | 0
Fair Value | 23,072 | 0
Corporate debt securities |  |
Available-for-Sale Portfolio |  |
Amortized Cost | 8,000 | 8,000
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 826 | 886
Fair Value | 7,174 | 7,114
Government agency collateralized mortgage obligations |  |
Available-for-Sale Portfolio |  |
Amortized Cost | 10,287 | 13,121
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | 800 | 852
Fair Value | 9,487 | $ 12,270
Held-to-Maturity Portfolio |  |
Fair Value | $ 0 |

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