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Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,058,471 | $ 1,051,313
Gross Unrealized Gains | 468 | 1,746
Gross Unrealized Losses | (85,100) | (83,751)
Fair Value | 973,839 | 969,308
Interest receivable | 3,800 | 3,800
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 123,296 | 144,292
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (9,847) | (10,506)
Fair Value | 113,449 | 133,786
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 25,310 | 33,342
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (524) | (829)
Fair Value | 24,786 | 32,513
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 569,806 | 507,942
Gross Unrealized Gains | 342 | 1,068
Gross Unrealized Losses | (50,823) | (48,071)
Fair Value | 519,325 | 460,939
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 42,301 | 44,707
Gross Unrealized Gains | 2 | 7
Gross Unrealized Losses | (7,005) | (6,537)
Fair Value | 35,298 | 38,177
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 272,741 | 290,775
Gross Unrealized Gains | 124 | 458
Gross Unrealized Losses | (16,325) | (17,808)
Fair Value | 256,540 | 273,425
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 25,017 | 30,255
Gross Unrealized Gains | 0 | 213
Gross Unrealized Losses | (576) | 0
Fair Value | $ 24,441 | $ 30,468

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