Note 3 - Securities (Tables)
|
6 Months Ended |
Jun. 30, 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 | |
| June 30, 2026 | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 104,704 | | | $ | 19 | | | $ | (10,213 | ) | | $ | 94,510 | |
| State and political subdivisions | | | 714,596 | | | | 2,962 | | | | (87,139 | ) | | | 630,419 | |
| Corporate bonds | | | 27,820 | | | | 246 | | | | (471 | ) | | | 27,595 | |
| Mortgage-backed securities | | | 631,434 | | | | 196 | | | | (83,977 | ) | | | 547,653 | |
| Collateralized mortgage obligations | | | 178,792 | | | | 301 | | | | (7,361 | ) | | | 171,732 | |
| Small Business Administration | | | 1,925 | | | | 0 | | | | (136 | ) | | | 1,789 | |
| Totals | | $ | 1,659,271 | | | $ | 3,724 | | | $ | (189,297 | ) | | $ | 1,473,698 | |
| | | | | | | 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 | | | Six Months Ended | |
| | | June 30, | | | June 30, | |
| (In Thousands of Dollars) | | 2026 | | | 2025 | | | 2026 | | | 2025 | |
| Proceeds | | $ | 0 | | | $ | 0 | | | $ | 0 | | | $ | 23,901 | |
| Gross gains | | | 0 | | | | 0 | | | | 0 | | | | 0 | |
| Gross losses | | | 0 | | | | 0 | | | | 0 | | | | (1,334 | ) |
|
| Investments Classified by Contractual Maturity Date [Table Text Block] |
| | | June 30, 2026 | |
| (In Thousands of Dollars) | | Amortized Cost | | | Fair Value | |
| Maturity | | | | | | | | |
| Within one year | | $ | 1,286 | | | $ | 1,298 | |
| One to five years | | | 106,550 | | | | 99,140 | |
| Five to ten years | | | 183,181 | | | | 170,404 | |
| Beyond ten years | | | 556,103 | | | | 481,682 | |
| Mortgage-backed, collateralized mortgage obligations and Small Business Administration securities | | | 812,151 | | | | 721,174 | |
| Total | | $ | 1,659,271 | | | $ | 1,473,698 | |
|
| 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 | |
| June 30, 2026 | | | | | | | | | | | | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | | | | | | |
| U.S. Treasury and U.S. government sponsored entities | | $ | 1,166 | | | $ | (9 | ) | | $ | 92,442 | | | $ | (10,204 | ) | | $ | 93,608 | | | $ | (10,213 | ) |
| State and political subdivisions | | | 95,438 | | | | (3,433 | ) | | | 406,107 | | | | (83,706 | ) | | | 501,545 | | | | (87,139 | ) |
| Corporate bonds | | | 14,899 | | | | (244 | ) | | | 5,345 | | | | (227 | ) | | | 20,244 | | | | (471 | ) |
| Mortgage-backed securities | | | 102,486 | | | | (1,716 | ) | | | 407,276 | | | | (82,261 | ) | | | 509,762 | | | | (83,977 | ) |
| Collateralized mortgage obligations | | | 68,206 | | | | (1,649 | ) | | | 71,540 | | | | (5,712 | ) | | | 139,746 | | | | (7,361 | ) |
| Small Business Administration | | | 0 | | | | 0 | | | | 1,789 | | | | (136 | ) | | | 1,789 | | | | (136 | ) |
| Total | | $ | 282,195 | | | $ | (7,051 | ) | | $ | 984,499 | | | $ | (182,246 | ) | | $ | 1,266,694 | | | $ | (189,297 | ) |
| | | 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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