Note 3 - Securities (Tables)
|
3 Months Ended |
Mar. 31, 2026 |
|---|
| Notes Tables |
|
| Debt Securities, Available-for-Sale [Table Text Block] |
| | | | | | | Gross | | | Gross | | | | | |
| | | Amortized | | | Unrealized | | | Unrealized | | | | | |
| (In Thousands of Dollars) | | Cost | | | Gains | | | Losses | | | Fair Value | |
| March 31, 2026 | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 104,720 | | | $ | 29 | | | $ | (9,851 | ) | | $ | 94,898 | |
| State and political subdivisions | | | 716,934 | | | | 1,710 | | | | (92,688 | ) | | | 625,956 | |
| Corporate bonds | | | 32,213 | | | | 140 | | | | (280 | ) | | | 32,073 | |
| Mortgage-backed securities | | | 635,441 | | | | 610 | | | | (83,320 | ) | | | 552,731 | |
| Collateralized mortgage obligations | | | 182,586 | | | | 617 | | | | (6,543 | ) | | | 176,660 | |
| Small Business Administration | | | 2,009 | | | | 0 | | | | (129 | ) | | | 1,880 | |
| Totals | | $ | 1,673,903 | | | $ | 3,106 | | | $ | (192,811 | ) | | $ | 1,484,198 | |
| | | | | | | Gross | | | Gross | | | | | |
| | | Amortized | | | Unrealized | | | Unrealized | | | | | |
| (In Thousands of Dollars) | | Cost | | | Gains | | | Losses | | | Fair Value | |
| December 31, 2025 | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 104,737 | | | $ | 45 | | | $ | (9,487 | ) | | $ | 95,295 | |
| State and political subdivisions | | | 589,236 | | | | 2,632 | | | | (88,171 | ) | | | 503,697 | |
| Corporate bonds | | | 13,171 | | | | 163 | | | | (289 | ) | | | 13,045 | |
| Mortgage-backed securities | | | 629,376 | | | | 731 | | | | (82,973 | ) | | | 547,134 | |
| Collateralized mortgage obligations | | | 186,494 | | | | 1,461 | | | | (5,739 | ) | | | 182,216 | |
| Small Business Administration | | | 2,210 | | | | 0 | | | | (140 | ) | | | 2,070 | |
| Totals | | $ | 1,525,224 | | | $ | 5,032 | | | $ | (186,799 | ) | | $ | 1,343,457 | |
|
| Gain (Loss) on Securities [Table Text Block] |
| | | Three Months Ended | |
| | | March 31, | |
| (In Thousands of Dollars) | | 2026 | | | 2025 | |
| Proceeds | | $ | 0 | | | $ | 23,901 | |
| Gross gains | | | 0 | | | | 0 | |
| Gross losses | | | 0 | | | | (1,334 | ) |
|
| Investments Classified by Contractual Maturity Date [Table Text Block] |
| | | March 31, 2026 | |
| (In Thousands of Dollars) | | Amortized Cost | | | Fair Value | |
| Maturity | | | | | | | | |
| Within one year | | $ | 4,668 | | | $ | 4,644 | |
| One to five years | | | 77,267 | | | | 72,915 | |
| Five to ten years | | | 209,826 | | | | 194,283 | |
| Beyond ten years | | | 562,106 | | | | 481,085 | |
| Mortgage-backed, collateralized mortgage obligations and Small Business Administration securities | | | 820,036 | | | | 731,271 | |
| Total | | $ | 1,673,903 | | | $ | 1,484,198 | |
|
| Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] |
| | | Less than 12 Months | | | 12 Months or Longer | | | Total | |
| | | Fair | | | Unrealized | | | Fair | | | Unrealized | | | Fair | | | Unrealized | |
| (In Thousands of Dollars) | | Value | | | Loss | | | Value | | | Loss | | | Value | | | Loss | |
| March 31, 2026 | | | | | | | | | | | | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 1,159 | | | $ | (11 | ) | | $ | 92,833 | | | $ | (9,840 | ) | | $ | 93,992 | | | $ | (9,851 | ) |
| State and political subdivisions | | | 155,312 | | | | (2,308 | ) | | | 404,333 | | | | (90,380 | ) | | | 559,645 | | | | (92,688 | ) |
| Corporate bonds | | | 18,386 | | | | (30 | ) | | | 6,805 | | | | (250 | ) | | | 25,191 | | | | (280 | ) |
| Mortgage-backed securities | | | 74,431 | | | | (958 | ) | | | 427,583 | | | | (82,362 | ) | | | 502,014 | | | | (83,320 | ) |
| Collateralized mortgage obligations | | | 56,177 | | | | (1,184 | ) | | | 69,827 | | | | (5,359 | ) | | | 126,004 | | | | (6,543 | ) |
| Small Business Administration | | | 0 | | | | 0 | | | | 1,880 | | | | (129 | ) | | | 1,880 | | | | (129 | ) |
| Total | | $ | 305,465 | | | $ | (4,491 | ) | | $ | 1,003,261 | | | $ | (188,320 | ) | | $ | 1,308,726 | | | $ | (192,811 | ) |
| | | Less than 12 Months | | | 12 Months or Longer | | | Total | |
| | | Fair | | | Unrealized | | | Fair | | | Unrealized | | | Fair | | | Unrealized | |
| (In Thousands of Dollars) | | Value | | | Loss | | | Value | | | Loss | | | Value | | | Loss | |
| December 31, 2025 | | | | | | | | | | | | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 100 | | | $ | 0 | | | $ | 93,211 | | | $ | (9,487 | ) | | $ | 93,311 | | | $ | (9,487 | ) |
| State and political subdivisions | | | 6,302 | | | | (1,360 | ) | | | 432,053 | | | | (86,811 | ) | | | 438,355 | | | | (88,171 | ) |
| Corporate bonds | | | 2,962 | | | | (44 | ) | | | 6,293 | | | | (245 | ) | | | 9,255 | | | | (289 | ) |
| Mortgage-backed securities | | | 48,965 | | | | (313 | ) | | | 437,859 | | | | (82,660 | ) | | | 486,824 | | | | (82,973 | ) |
| Collateralized mortgage obligations | | | 50,887 | | | | (621 | ) | | | 69,006 | | | | (5,118 | ) | | | 119,893 | | | | (5,739 | ) |
| Small Business Administration | | | 0 | | | | 0 | | | | 2,070 | | | | (140 | ) | | | 2,070 | | | | (140 | ) |
| Total | | $ | 109,216 | | | $ | (2,338 | ) | | $ | 1,040,492 | | | $ | (184,461 | ) | | $ | 1,149,708 | | | $ | (186,799 | ) |
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