| Summary of Deposits and Percentage Change in Deposits [Table Text Block] |
| | | | | | | | | | | | | | | | | | | Percent | |
| | | March 31, 2025 | | | December 31, 2024 | | | Increase | |
| (Dollars in thousands) | | Balance | | | % | | | Balance | | | % | | | (Decrease) | |
| | | | | | | | | | | | | | | | | | | | | |
| Noninterest-bearing checking | | $ | 1,173,499 | | | | 25.1 | % | | $ | 1,264,523 | | | | 26.9 | % | | | (7.2 | )% |
| Interest-bearing checking | | | 751,344 | | | | 16.0 | | | | 738,291 | | | | 15.7 | | | | 1.8 | |
| Money market | | | 1,566,569 | | | | 33.5 | | | | 1,516,436 | | | | 32.3 | | | | 3.3 | |
| Savings | | | 226,361 | | | | 4.8 | | | | 221,900 | | | | 4.7 | | | | 2.0 | |
| Time, under $100,000 | | | 213,281 | | | | 4.6 | | | | 207,534 | | | | 4.4 | | | | 2.8 | |
| Time, $100,000 and over | | | 601,036 | | | | 12.8 | | | | 599,983 | | | | 12.8 | | | | 0.2 | |
| Total local deposits | | | 4,532,090 | | | | 96.8 | | | | 4,548,667 | | | | 96.8 | | | | (0.4 | ) |
| | | | | | | | | | | | | | | | | | | | | |
| Out-of-area time, $100,000 and over | | | 149,695 | | | | 3.2 | | | | 149,699 | | | | 3.2 | | | | (0.0 | ) |
| | | | | | | | | | | | | | | | | | | | | |
| Total deposits | | $ | 4,681,785 | | | | 100.0 | % | | $ | 4,698,366 | | | | 100.0 | % | | | (0.4 | )% |
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