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v3.25.1

Note 3 - Investment Securities (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2025
Notes Tables |
Debt Securities, Available-for-sale and Held-to-maturity [Table Text Block] |
|  | At March 31, 2025 |
|  |  |  |  |  | Gross |  |  | Gross |  |  |  |  |
|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  | Fair |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Value |
|  | (In thousands) |
Debt securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential mortgage-backed securities ("MBS") |  | $ | 218,825 |  |  | $ | 4 |  |  | $ | (14,487 | ) |  | $ | 204,342 |
Agency commercial MBS |  |  | 46,057 |  |  |  | 451 |  |  |  | (6 | ) |  |  | 46,502 |
Securities of U.S. Government sponsored entities |  |  | 311,809 |  |  |  | 19 |  |  |  | (12,106 | ) |  |  | 299,722 |
Obligations of states and political subdivisions |  |  | 62,177 |  |  |  | 7 |  |  |  | (1,603 | ) |  |  | 60,581 |
Corporate securities |  |  | 1,967,432 |  |  |  | - |  |  |  | (164,641 | ) |  |  | 1,802,791 |
Collateralized loan obligations |  |  | 823,921 |  |  |  | 514 |  |  |  | (2,324 | ) |  |  | 822,111 |
Total debt securities available for sale |  |  | 3,430,221 |  |  |  | 995 |  |  |  | (195,167 | ) |  |  | 3,236,049 |
Debt securities held to maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential MBS |  |  | 53,528 |  |  |  | 23 |  |  |  | (3,418 | ) |  |  | 50,133 |
Obligations of states and political subdivisions |  |  | 48,675 |  |  |  | 12 |  |  |  | (203 | ) |  |  | 48,484 |
Corporate securities |  |  | 737,146 |  |  |  | 277 |  |  |  | (22,915 | ) |  |  | 714,508 |
Total debt securities held to maturity |  |  | 839,349 |  |  |  | 312 |  |  |  | (26,536 | ) |  |  | 813,125 |
Total |  | $ | 4,269,570 |  |  | $ | 1,307 |  |  | $ | (221,703 | ) |  | $ | 4,049,174 |
|  | At December 31, 2024 |
|  |  |  |  |  | Gross |  |  | Gross |  |  |  |  |
|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  | Fair |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Value |
|  | (In thousands) |
Debt securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential MBS |  | $ | 229,050 |  |  | $ | 1 |  |  | $ | (17,991 | ) |  | $ | 211,060 |
Agency commercial MBS |  |  | 7,098 |  |  |  | - |  |  |  | (132 | ) |  |  | 6,966 |
Securities of U.S. Government sponsored entities |  |  | 311,201 |  |  |  | 1 |  |  |  | (19,085 | ) |  |  | 292,117 |
U.S. Treasury Securities |  |  | 4,945 |  |  |  | 10 |  |  |  | - |  |  |  | 4,955 |
Obligations of states and political subdivisions |  |  | 63,878 |  |  |  | 9 |  |  |  | (1,701 | ) |  |  | 62,186 |
Corporate securities |  |  | 2,031,144 |  |  |  | 127 |  |  |  | (195,334 | ) |  |  | 1,835,937 |
Collateralized loan obligations |  |  | 987,155 |  |  |  | 642 |  |  |  | (5,208 | ) |  |  | 982,589 |
Total debt securities available for sale |  |  | 3,634,471 |  |  |  | 790 |  |  |  | (239,451 | ) |  |  | 3,395,810 |
Debt securities held to maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential MBS |  |  | 57,927 |  |  |  | 23 |  |  |  | (4,218 | ) |  |  | 53,732 |
Obligations of states and political subdivisions |  |  | 51,261 |  |  |  | 12 |  |  |  | (377 | ) |  |  | 50,896 |
Corporate securities |  |  | 735,447 |  |  |  | - |  |  |  | (32,237 | ) |  |  | 703,210 |
Total debt securities held to maturity |  |  | 844,635 |  |  |  | 35 |  |  |  | (36,832 | ) |  |  | 807,838 |
Total |  | $ | 4,479,106 |  |  | $ | 825 |  |  | $ | (276,283 | ) |  | $ | 4,203,648 |
Investments Classified by Contractual Maturity Date [Table Text Block] |
|  | At March 31, 2025 |
|  | Debt Securities Available |  |  | Debt Securities Held |
|  | for Sale |  |  | to Maturity |
|  | Amortized |  |  | Fair |  |  | Amortized |  |  | Fair |
|  | Cost |  |  | Value |  |  | Cost |  |  | Value |
|  | (In thousands) |
Maturity in years: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1 year or less |  | $ | 83,272 |  |  | $ | 82,874 |  |  | $ | 18,877 |  |  | $ | 18,819 |
Over 1 to 5 years |  |  | 1,093,030 |  |  |  | 1,039,910 |  |  |  | 379,408 |  |  |  | 376,571 |
Over 5 to 10 years |  |  | 1,165,116 |  |  |  | 1,040,310 |  |  |  | 387,536 |  |  |  | 367,602 |
Subtotal |  |  | 2,341,418 |  |  |  | 2,163,094 |  |  |  | 785,821 |  |  |  | 762,992 |
Collateralized loan obligations |  |  | 823,921 |  |  |  | 822,111 |  |  |  | - |  |  |  | - |
Agency residential MBS |  |  | 218,825 |  |  |  | 204,342 |  |  |  | 53,528 |  |  |  | 50,133 |
Agency commercial MBS |  |  | 46,057 |  |  |  | 46,502 |  |  |  | - |  |  |  | - |
Total |  | $ | 3,430,221 |  |  | $ | 3,236,049 |  |  | $ | 839,349 |  |  | $ | 813,125 |
|  | At December 31, 2024 |
|  | Debt Securities Available |  |  | Debt Securities Held |
|  | for Sale |  |  | to Maturity |
|  | Amortized |  |  | Fair |  |  | Amortized |  |  | Fair |
|  | Cost |  |  | Value |  |  | Cost |  |  | Value |
|  | (In thousands) |
Maturity in years: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1 year or less |  | $ | 124,667 |  |  | $ | 124,448 |  |  | $ | 13,508 |  |  | $ | 13,468 |
Over 1 to 5 years |  |  | 993,874 |  |  |  | 940,578 |  |  |  | 347,566 |  |  |  | 342,500 |
Over 5 to 10 years |  |  | 1,292,627 |  |  |  | 1,130,169 |  |  |  | 425,634 |  |  |  | 398,138 |
Subtotal |  |  | 2,411,168 |  |  |  | 2,195,195 |  |  |  | 786,708 |  |  |  | 754,106 |
Collateralized loan obligations |  |  | 987,155 |  |  |  | 982,589 |  |  |  | - |  |  |  | - |
Agency residential MBS |  |  | 229,050 |  |  |  | 211,060 |  |  |  | 57,927 |  |  |  | 53,732 |
Agency commercial MBS |  |  | 7,098 |  |  |  | 6,966 |  |  |  | - |  |  |  | - |
Total |  | $ | 3,634,471 |  |  | $ | 3,395,810 |  |  | $ | 844,635 |  |  | $ | 807,838 |
Schedule of Unrealized Loss on Investments 1 [Table Text Block] |
|  | Debt Securities Available for Sale |
|  | At March 31, 2025 |
|  | No. of |  |  | Less than 12 months |  |  | No. of |  |  | 12 months or longer |  |  | No. of |  |  | Total |
|  | Investment |  |  |  |  |  |  | Unrealized |  |  | Investment |  |  |  |  |  |  | Unrealized |  |  | Investment |  |  |  |  |  |  | Unrealized |
|  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |
|  | ($ in thousands) |
Agency residential MBS |  |  | 10 |  |  | $ | 13,725 |  |  | $ | (420 | ) |  |  | 102 |  |  | $ | 186,156 |  |  | $ | (14,067 | ) |  |  | 112 |  |  | $ | 199,881 |  |  | $ | (14,487 | )
Agency commercial MBS |  |  | 1 |  |  |  | 3,220 |  |  |  | (6 | ) |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 1 |  |  |  | 3,220 |  |  |  | (6 | )
Securities of U.S. Government sponsored entities |  |  | 1 |  |  |  | 1,937 |  |  |  | (1 | ) |  |  | 19 |  |  |  | 282,994 |  |  |  | (12,105 | ) |  |  | 20 |  |  |  | 284,931 |  |  |  | (12,106 | )
Obligations of states and political subdivisions |  |  | 4 |  |  |  | 4,668 |  |  |  | (17 | ) |  |  | 39 |  |  |  | 49,171 |  |  |  | (1,586 | ) |  |  | 43 |  |  |  | 53,839 |  |  |  | (1,603 | )
Corporate securities |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 134 |  |  |  | 1,802,791 |  |  |  | (164,641 | ) |  |  | 134 |  |  |  | 1,802,791 |  |  |  | (164,641 | )
Collateralized loan obligations |  |  | 3 |  |  |  | 38,770 |  |  |  | (66 | ) |  |  | 24 |  |  |  | 202,002 |  |  |  | (2,258 | ) |  |  | 27 |  |  |  | 240,772 |  |  |  | (2,324 | )
Total |  |  | 19 |  |  | $ | 62,320 |  |  | $ | (510 | ) |  |  | 318 |  |  | $ | 2,523,114 |  |  | $ | (194,657 | ) |  |  | 337 |  |  | $ | 2,585,434 |  |  | $ | (195,167 | )
|  | Debt Securities Held to Maturity |
|  | At March 31, 2025 |
|  | No. of |  |  | Less than 12 months |  |  | No. of |  |  | 12 months or longer |  |  | No. of |  |  | Total |
|  | Investment |  |  |  |  |  |  | Unrecognized |  |  | Investment |  |  |  |  |  |  | Unrecognized |  |  | Investment |  |  |  |  |  |  | Unrecognized |
|  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |
|  | ($ in thousands) |
Agency residential MBS |  |  | - |  |  | $ | - |  |  | $ | - |  |  |  | 76 |  |  | $ | 49,121 |  |  | $ | (3,418 | ) |  |  | 76 |  |  | $ | 49,121 |  |  | $ | (3,418 | )
Obligations of states and political subdivisions |  |  | 13 |  |  |  | 8,648 |  |  |  | (19 | ) |  |  | 27 |  |  |  | 24,879 |  |  |  | (184 | ) |  |  | 40 |  |  |  | 33,527 |  |  |  | (203 | )
Corporate securities |  |  | 18 |  |  |  | 167,402 |  |  |  | (1,597 | ) |  |  | 35 |  |  |  | 459,147 |  |  |  | (21,318 | ) |  |  | 53 |  |  |  | 626,549 |  |  |  | (22,915 | )
Total |  |  | 31 |  |  | $ | 176,050 |  |  | $ | (1,616 | ) |  |  | 138 |  |  | $ | 533,147 |  |  | $ | (24,920 | ) |  |  | 169 |  |  | $ | 709,197 |  |  | $ | (26,536 | )
|  | Debt Securities Available for Sale |
|  | At December 31, 2024 |
|  | No. of |  |  | Less than 12 months |  |  | No. of |  |  | 12 months or longer |  |  | No. of |  |  | Total |
|  | Investment |  |  |  |  |  |  | Unrealized |  |  | Investment |  |  |  |  |  |  | Unrealized |  |  | Investment |  |  |  |  |  |  | Unrealized |
|  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |
|  | ($ in thousands) |
Agency residential MBS |  |  | 12 |  |  | $ | 18,030 |  |  | $ | (471 | ) |  |  | 103 |  |  | $ | 192,963 |  |  | $ | (17,520 | ) |  |  | 115 |  |  | $ | 210,993 |  |  | $ | (17,991 | )
Agency commercial MBS |  |  | 2 |  |  |  | 6,966 |  |  |  | (132 | ) |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 2 |  |  |  | 6,966 |  |  |  | (132 | )
Securities of U.S. Government sponsored entities |  |  | 3 |  |  |  | 12,085 |  |  |  | (53 | ) |  |  | 19 |  |  |  | 275,467 |  |  |  | (19,032 | ) |  |  | 22 |  |  |  | 287,552 |  |  |  | (19,085 | )
Obligations of states and political subdivisions |  |  | 2 |  |  |  | 2,764 |  |  |  | (21 | ) |  |  | 40 |  |  |  | 51,759 |  |  |  | (1,680 | ) |  |  | 42 |  |  |  | 54,523 |  |  |  | (1,701 | )
Corporate securities |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 138 |  |  |  | 1,824,327 |  |  |  | (195,334 | ) |  |  | 138 |  |  |  | 1,824,327 |  |  |  | (195,334 | )
Collateralized loan obligations |  |  | 3 |  |  |  | 26,825 |  |  |  | (15 | ) |  |  | 32 |  |  |  | 309,249 |  |  |  | (5,193 | ) |  |  | 35 |  |  |  | 336,074 |  |  |  | (5,208 | )
Total |  |  | 22 |  |  | $ | 66,670 |  |  | $ | (692 | ) |  |  | 332 |  |  | $ | 2,653,765 |  |  | $ | (238,759 | ) |  |  | 354 |  |  | $ | 2,720,435 |  |  | $ | (239,451 | )
|  | Debt Securities Held to Maturity |
|  | At December 31, 2024 |
|  | No. of |  |  | Less than 12 months |  |  | No. of |  |  | 12 months or longer |  |  | No. of |  |  | Total |
|  | Investment |  |  |  |  |  |  | Unrecognized |  |  | Investment |  |  |  |  |  |  | Unrecognized |  |  | Investment |  |  |  |  |  |  | Unrecognized |
|  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |  |  | Positions |  |  | Fair Value |  |  | Losses |
|  | ($ in thousands) |
Agency residential MBS |  |  | - |  |  | $ | - |  |  | $ | - |  |  |  | 80 |  |  | $ | 52,771 |  |  | $ | (4,218 | ) |  |  | 80 |  |  | $ | 52,771 |  |  | $ | (4,218 | )
Obligations of states and political subdivisions |  |  | 24 |  |  |  | 15,822 |  |  |  | (78 | ) |  |  | 26 |  |  |  | 25,814 |  |  |  | (299 | ) |  |  | 50 |  |  |  | 41,636 |  |  |  | (377 | )
Corporate securities |  |  | 23 |  |  |  | 251,790 |  |  |  | (4,230 | ) |  |  | 35 |  |  |  | 451,420 |  |  |  | (28,007 | ) |  |  | 58 |  |  |  | 703,210 |  |  |  | (32,237 | )
Total |  |  | 47 |  |  | $ | 267,612 |  |  | $ | (4,308 | ) |  |  | 141 |  |  | $ | 530,005 |  |  | $ | (32,524 | ) |  |  | 188 |  |  | $ | 797,617 |  |  | $ | (36,832 | )
Debt Securities, Held-to-Maturity, Allowance for Credit Loss [Table Text Block] |
|  | For the Three Months Ended March 31, |
|  | 2025 |  |  | 2024 |
|  | (In thousands) |
Allowance for credit losses: |  |  |  |  |  |  |  |
Beginning balance |  | $ | 1 |  |  | $ | 1 |
Provision |  |  | - |  |  |  | - |
Chargeoffs |  |  | - |  |  |  | - |
Recoveries |  |  | - |  |  |  | - |
Total ending balance |  | $ | 1 |  |  | $ | 1 |
Debt Securities, Held-to-Maturity, Credit Quality Indicator [Table Text Block] |
|  | Credit Risk Profile by Credit Rating |
|  | At March 31, 2025 |
|  | AAA/AA/A |  |  | BBB+/BBB |  |  | Not Rated |  |  | Total |
|  | (In thousands) |
Agency residential MBS |  | $ | 53,064 |  |  | $ | - |  |  | $ | 464 |  |  | $ | 53,528 |
Obligations of states and political subdivisions |  |  | 48,675 |  |  |  | - |  |  |  | - |  |  |  | 48,675 |
Corporate securities |  |  | 554,871 |  |  |  | 182,275 |  |  |  | - |  |  |  | 737,146 |
Total |  | $ | 656,610 |  |  | $ | 182,275 |  |  | $ | 464 |  |  | $ | 839,349 |
Interest Income from Investments [Table Text Block] |
|  | For the Three Months |
|  | Ended March 31, |
|  | 2025 |  |  | 2024 |
|  | (In thousands) |
Taxable |  | $ | 41,280 |  |  | $ | 54,145 |
Tax-exempt from regular federal income tax |  |  | 839 |  |  |  | 994 |
Total interest income from investment securities |  | $ | 42,119 |  |  | $ | 55,139 |

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