Note 4 - Investment Securities (Tables)
|
3 Months Ended |
Mar. 31, 2026 |
|---|
| Notes Tables |
|
| Debt Securities, Available-for-Sale [Table Text Block] |
| | | | | | | | | | | | | | | | | | | Allowance | |
| | | | | | | | | | | | | | | | | | | for | |
| | | | | | | Gross | | | Gross | | | | | | | Investment | |
| | | Amortized | | | Unrealized | | | Unrealized | | | Fair | | | Credit | |
| | | Cost | | | Gains | | | Losses | | | Value | | | Losses | |
| | | (dollars in thousands) | |
| March 31, 2026 | | | | | | | | | | | | | | | | | | | | |
| Available-for-sale securities: | | | | | | | | | | | | | | | | | | | | |
| Federal agency obligations | | $ | 362,898 | | | $ | 2,088 | | | $ | (10,183 | ) | | $ | 354,803 | | | $ | - | |
| Residential mortgage pass-through securities | | | 637,699 | | | | 3,883 | | | | (45,424 | ) | | | 596,158 | | | | - | |
| Commercial mortgage pass-through securities | | | 29,963 | | | | - | | | | (3,335 | ) | | | 26,628 | | | | - | |
| Obligations of U.S. states and political subdivisions | | | 219,262 | | | | 2,697 | | | | (17,396 | ) | | | 204,563 | | | | - | |
| Corporate bonds and notes | | | 13,500 | | | | 8 | | | | (42 | ) | | | 13,466 | | | | - | |
| Asset-backed securities | | | 508 | | | | 1 | | | | (3 | ) | | | 506 | | | | - | |
| Other securities | | | 260 | | | | - | | | | - | | | | 260 | | | | - | |
| Total available-for-sale securities | | $ | 1,264,090 | | | $ | 8,677 | | | $ | (76,383 | ) | | $ | 1,196,384 | | | $ | - | |
| | | | | | | | | | | | | | | | | | | | | |
| December 31, 2025 | | | | | | | | | | | | | | | | | | | | |
| Available-for-sale securities: | | | | | | | | | | | | | | | | | | | | |
| Federal agency obligations | | $ | 398,392 | | | $ | 2,467 | | | $ | (9,669 | ) | | $ | 391,190 | | | $ | - | |
| Residential mortgage pass-through securities | | | 644,811 | | | | 5,391 | | | | (43,058 | ) | | | 607,144 | | | | - | |
| Commercial mortgage pass-through securities | | | 30,124 | | | | - | | | | (3,155 | ) | | | 26,969 | | | | - | |
| Obligations of U.S. states and political subdivisions | | | 221,545 | | | | 5,385 | | | | (14,521 | ) | | | 212,409 | | | | - | |
| Corporate bonds and notes | | | 12,500 | | | | 22 | | | | (3 | ) | | | 12,519 | | | | - | |
| Asset-backed securities | | | 528 | | | | - | | | | (3 | ) | | | 525 | | | | - | |
| Other securities | | | 182 | | | | - | | | | - | | | | 182 | | | | - | |
| Total available-for-sale securities | | $ | 1,308,082 | | | $ | 13,265 | | | $ | (70,409 | ) | | $ | 1,250,938 | | | $ | - | |
|
| Investments Classified by Contractual Maturity Date [Table Text Block] |
| | | March 31, 2026 | |
| | | Amortized | | | Fair | |
| | | Cost | | | Value | |
| | | (dollars in thousands) | |
| Available-for-sale securities | | | | | | | | |
| Due in one year or less | | $ | 4,592 | | | $ | 4,600 | |
| Due after one year through five years | | | 28,739 | | | | 29,011 | |
| Due after five years through ten years | | | 68,144 | | | | 68,218 | |
| Due after ten years | | | 494,693 | | | | 471,509 | |
| Residential mortgage pass-through securities | | | 637,699 | | | | 596,158 | |
| Commercial mortgage pass-through securities | | | 29,963 | | | | 26,628 | |
| Other securities | | | 260 | | | | 260 | |
| Total available-for-sale securities | | $ | 1,264,090 | | | $ | 1,196,384 | |
|
| Unrealized Gain (Loss) on Investments [Table Text Block] |
| | | March 31, 2026 | |
| | | Total | | | Less than 12 Months | | | 12 Months or Longer | |
| | | Fair | | | Unrealized | | | Fair | | | Unrealized | | | Fair | | | Unrealized | |
| | | Value | | | Losses | | | Value | | | Losses | | | Value | | | Losses | |
| | | (dollars in thousands) | |
| Available-for-sale securities: | | | | | | | | | | | | | | | | | | | | | | | | |
| Federal agency obligations | | $ | 77,588 | | | $ | (10,183 | ) | | $ | 45,048 | | | $ | (433 | ) | | $ | 32,540 | | | $ | (9,750 | ) |
| Residential mortgage pass-through securities | | | 386,362 | | | | (45,424 | ) | | | 83,827 | | | | (1,200 | ) | | | 302,535 | | | | (44,224 | ) |
| Commercial mortgage pass-through securities | | | 26,628 | | | | (3,335 | ) | | | 5,267 | | | | (188 | ) | | | 21,361 | | | | (3,147 | ) |
| Obligations of U.S. states and political subdivisions | | | 100,319 | | | | (17,396 | ) | | | 15,319 | | | | (406 | ) | | | 85,000 | | | | (16,990 | ) |
| Corporate bonds and notes | | | 6,958 | | | | (42 | ) | | | 6,958 | | | | (42 | ) | | | - | | | | - | |
| Asset-backed securities | | | 270 | | | | (3 | ) | | | - | | | | - | | | | 270 | | | | (3 | ) |
| Total available-for-sale securities | | $ | 598,125 | | | $ | (76,383 | ) | | $ | 156,419 | | | $ | (2,269 | ) | | $ | 441,706 | | | $ | (74,114 | ) |
| | | December 31, 2025 | |
| | | Total | | | Less than 12 Months | | | 12 Months or Longer | |
| | | Fair | | | Unrealized | | | Fair | | | Unrealized | | | Fair | | | Unrealized | |
| | | Value | | | Losses | | | Value | | | Losses | | | Value | | | Losses | |
| | | (dollars in thousands) | |
| Available-for-sale securities: | | | | | | | | | | | | | | | | | | | | | | | | |
| Federal agency obligations | | $ | 135,103 | | | $ | (9,669 | ) | | $ | 101,610 | | | $ | (246 | ) | | $ | 33,493 | | | $ | (9,423 | ) |
| Residential mortgage pass-through securities | | | 331,799 | | | | (43,058 | ) | | | 5,547 | | | | (45 | ) | | | 326,252 | | | | (43,013 | ) |
| Commercial mortgage pass-through securities | | | 26,969 | | | | (3,155 | ) | | | 5,421 | | | | (96 | ) | | | 21,548 | | | | (3,059 | ) |
| Obligations of U.S. states and political subdivisions | | | 103,918 | | | | (14,521 | ) | | | 4,276 | | | | (20 | ) | | | 99,642 | | | | (14,501 | ) |
| Corporate bonds and notes | | | 1,997 | | | | (3 | ) | | | 1,997 | | | | (3 | ) | | | - | | | | - | |
| Asset-backed securities | | | 525 | | | | (3 | ) | | | 242 | | | | - | | | | 283 | | | | (3 | ) |
| Total available-for-sale securities | | $ | 600,311 | | | $ | (70,409 | ) | | $ | 119,093 | | | $ | (410 | ) | | $ | 481,218 | | | $ | (69,999 | ) |
|