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Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 1,064,347 | $ 1,058,154
Gross Unrealized Gains | 3,372 | 990
Gross Unrealized Losses | (57,769) | (72,729)
Fair Value | 1,009,950 | 986,415
Interest receivable | 3,400 | 3,700
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 96,881 | 97,045
Gross Unrealized Gains | 55 | 0
Gross Unrealized Losses | (3,331) | (4,277)
Fair Value | 93,605 | 92,768
Obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 10,239 | 15,260
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (112) | (189)
Fair Value | 10,127 | 15,071
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 686,862 | 643,690
Gross Unrealized Gains | 2,389 | 872
Gross Unrealized Losses | (40,433) | (48,278)
Fair Value | 648,818 | 596,284
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 39,156 | 40,109
Gross Unrealized Gains | 5 | 3
Gross Unrealized Losses | (6,018) | (6,905)
Fair Value | 33,143 | 33,207
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 226,228 | 237,270
Gross Unrealized Gains | 923 | 115
Gross Unrealized Losses | (7,866) | (12,587)
Fair Value | 219,285 | 224,798
Obligations of states and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 4,981 | 24,780
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (9) | (493)
Fair Value | $ 4,972 | $ 24,287

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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