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v3.25.2

Note 3 - Investment Securities (Tables) | 6 Months Ended
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Jun. 30, 2025
Notes Tables |
Debt Securities, Available-for-sale and Held-to-maturity [Table Text Block] |
|  | At June 30, 2025 |
|  |  |  |  |  | Gross |  |  | Gross |  |  |  |  |
|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  | Fair |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Value |
|  | (In thousands) |
Debt securities available for sale: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential mortgage-backed securities ("MBS") |  | $ | 208,198 |  |  | $ | 1 |  |  | $ | (12,921 | ) |  | $ | 195,278 |
Agency commercial MBS |  |  | 95,966 |  |  |  | 364 |  |  |  | (65 | ) |  |  | 96,265 |
Securities of U.S. Government sponsored entities |  |  | 312,417 |  |  |  | 27 |  |  |  | (10,541 | ) |  |  | 301,903 |
Obligations of states and political subdivisions |  |  | 61,987 |  |  |  | 8 |  |  |  | (1,160 | ) |  |  | 60,835 |
Corporate securities |  |  | 1,931,579 |  |  |  | - |  |  |  | (139,558 | ) |  |  | 1,792,021 |
Collateralized loan obligations |  |  | 782,050 |  |  |  | 385 |  |  |  | (2,288 | ) |  |  | 780,147 |
Total debt securities available for sale |  |  | 3,392,197 |  |  |  | 785 |  |  |  | (166,533 | ) |  |  | 3,226,449 |
Debt securities held to maturity: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Agency residential MBS |  |  | 49,878 |  |  |  | 23 |  |  |  | (2,887 | ) |  |  | 47,014 |
Obligations of states and political subdivisions |  |  | 45,716 |  |  |  | 8 |  |  |  | (131 | ) |  |  | 45,593 |
Corporate securities |  |  | 738,846 |  |  |  | 1,162 |  |  |  | (14,896 | ) |  |  | 725,112 |
Total debt securities held to maturity |  |  | 834,440 |  |  |  | 1,193 |  |  |  | (17,914 | ) |  |  | 817,719 |
Total |  | $ | 4,226,637 |  |  | $ | 1,978 |  |  | $ | (184,447 | ) |  | $ | 4,044,168 |
|  | 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 June 30, 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 |  | $ | 126,847 |  |  | $ | 126,010 |  |  | $ | 26,288 |  |  | $ | 26,218 |
Over 1 to 5 years |  |  | 1,207,932 |  |  |  | 1,150,997 |  |  |  | 400,042 |  |  |  | 399,891 |
Over 5 to 10 years |  |  | 971,204 |  |  |  | 877,752 |  |  |  | 358,232 |  |  |  | 344,596 |
Subtotal |  |  | 2,305,983 |  |  |  | 2,154,759 |  |  |  | 784,562 |  |  |  | 770,705 |
Collateralized loan obligations |  |  | 782,050 |  |  |  | 780,147 |  |  |  | - |  |  |  | - |
Agency residential MBS |  |  | 208,198 |  |  |  | 195,278 |  |  |  | 49,878 |  |  |  | 47,014 |
Agency commercial MBS |  |  | 95,966 |  |  |  | 96,265 |  |  |  | - |  |  |  | - |
Total |  | $ | 3,392,197 |  |  | $ | 3,226,449 |  |  | $ | 834,440 |  |  | $ | 817,719 |
|  | 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 June 30, 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 |  |  | 9 |  |  | $ | 17,873 |  |  | $ | (549 | ) |  |  | 102 |  |  | $ | 177,288 |  |  | $ | (12,372 | ) |  |  | 111 |  |  | $ | 195,161 |  |  | $ | (12,921 | )
Agency commercial MBS |  |  | 6 |  |  |  | 26,624 |  |  |  | (65 | ) |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 6 |  |  |  | 26,624 |  |  |  | (65 | )
Securities of U.S. Government sponsored entities |  |  | 2 |  |  |  | 6,512 |  |  |  | (2 | ) |  |  | 19 |  |  |  | 285,159 |  |  |  | (10,539 | ) |  |  | 21 |  |  |  | 291,671 |  |  |  | (10,541 | )
Obligations of states and political subdivisions |  |  | 4 |  |  |  | 4,649 |  |  |  | (15 | ) |  |  | 39 |  |  |  | 49,443 |  |  |  | (1,145 | ) |  |  | 43 |  |  |  | 54,092 |  |  |  | (1,160 | )
Corporate securities |  |  | - |  |  |  | - |  |  |  | - |  |  |  | 132 |  |  |  | 1,792,021 |  |  |  | (139,558 | ) |  |  | 132 |  |  |  | 1,792,021 |  |  |  | (139,558 | )
Collateralized loan obligations |  |  | 7 |  |  |  | 93,767 |  |  |  | (191 | ) |  |  | 22 |  |  |  | 187,138 |  |  |  | (2,097 | ) |  |  | 29 |  |  |  | 280,905 |  |  |  | (2,288 | )
Total |  |  | 28 |  |  | $ | 149,425 |  |  | $ | (822 | ) |  |  | 314 |  |  | $ | 2,491,049 |  |  | $ | (165,711 | ) |  |  | 342 |  |  | $ | 2,640,474 |  |  | $ | (166,533 | )
|  | Debt Securities Held to Maturity |
|  | At June 30, 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 |  |  | - |  |  | $ | - |  |  | $ | - |  |  |  | 69 |  |  | $ | 46,038 |  |  | $ | (2,887 | ) |  |  | 69 |  |  | $ | 46,038 |  |  | $ | (2,887 | )
Obligations of states and political subdivisions |  |  | 11 |  |  |  | 8,534 |  |  |  | (8 | ) |  |  | 24 |  |  |  | 22,673 |  |  |  | (123 | ) |  |  | 35 |  |  |  | 31,207 |  |  |  | (131 | )
Corporate securities |  |  | 10 |  |  |  | 51,063 |  |  |  | (234 | ) |  |  | 34 |  |  |  | 452,940 |  |  |  | (14,662 | ) |  |  | 44 |  |  |  | 504,003 |  |  |  | (14,896 | )
Total |  |  | 21 |  |  | $ | 59,597 |  |  | $ | (242 | ) |  |  | 127 |  |  | $ | 521,651 |  |  | $ | (17,672 | ) |  |  | 148 |  |  | $ | 581,248 |  |  | $ | (17,914 | )
|  | 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 Six Months Ended June 30, |
|  | 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 June 30, 2025 |
|  | AAA/AA/A |  |  | BBB+/BBB |  |  | Not Rated |  |  | Total |
|  | (In thousands) |
Agency residential MBS |  | $ | 49,423 |  |  | $ | - |  |  | $ | 455 |  |  | $ | 49,878 |
Obligations of states and political subdivisions |  |  | 45,716 |  |  |  | - |  |  |  | - |  |  |  | 45,716 |
Corporate securities |  |  | 556,117 |  |  |  | 182,729 |  |  |  | - |  |  |  | 738,846 |
Total |  | $ | 651,256 |  |  | $ | 182,729 |  |  | $ | 455 |  |  | $ | 834,440 |
Interest Income from Investments [Table Text Block] |
|  | For the Three Months |  |  | For the Six Months |
|  | Ended June 30, |
|  | 2025 |  |  | 2024 |  |  | 2025 |  |  | 2024 |
|  | (In thousands) |
Taxable |  | $ | 38,847 |  |  | $ | 51,804 |  |  | $ | 80,127 |  |  | $ | 105,949 |
Tax-exempt from regular federal income tax |  |  | 824 |  |  |  | 953 |  |  |  | 1,663 |  |  |  | 1,947 |
Total interest income from investment securities |  | $ | 39,671 |  |  | $ | 52,757 |  |  | $ | 81,790 |  |  | $ | 107,896 |

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