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Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 7,653,341 | $ 7,183,969 |
Nonaccrual | 22,947 | 19,052 | $ 66,291
Current |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 7,615,273 | 7,144,576 |
Total Past Due Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 38,068 | 39,393 |
30-59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 7,247 | 18,093 |
60-89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 7,874 | 2,248 |
Commercial Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,659,135 | 2,538,839 |
Nonaccrual | 6,320 | 7,100 | 31,488
Commercial Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,436,183 | 1,510,392 |
Nonaccrual | 878 | 283 | 15,239
Commercial Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 350,583 | 381,963 |
Nonaccrual | 4,960 | 384 | 2,471
Commercial Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,360,765 | 1,205,944 |
Nonaccrual | 4,147 | 4,490 | 9,641
Commercial Loans | Current | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,649,412 | 2,523,315 |
Commercial Loans | Current | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,435,301 | 1,505,805 |
Commercial Loans | Current | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 345,623 | 381,579 |
Commercial Loans | Current | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,351,048 | 1,199,586 |
Commercial Loans | Total Past Due Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 9,723 | 15,524 |
Commercial Loans | Total Past Due Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 882 | 4,587 |
Commercial Loans | Total Past Due Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 4,960 | 384 |
Commercial Loans | Total Past Due Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 9,717 | 6,358 |
Commercial Loans | 30-59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 8,424 |
Commercial Loans | 30-59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 4 | 4,304 |
Commercial Loans | 30-59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 30-59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 3,525 | 1,583 |
Commercial Loans | 60-89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 3,403 | 0 |
Commercial Loans | 60-89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 60-89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial Loans | 60-89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,045 | 285 |
Consumer Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,731,778 | 1,421,953 |
Nonaccrual | 6,312 | 6,526 | 7,294
Consumer Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 114,897 | 124,878 |
Nonaccrual | 330 | 269 | $ 158
Consumer Loans | Current | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,719,751 | 1,409,907 |
Consumer Loans | Current | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 114,138 | 124,384 |
Consumer Loans | Total Past Due Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 12,027 | 12,046 |
Consumer Loans | Total Past Due Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 759 | 494 |
Consumer Loans | 30-59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 3,352 | 3,617 |
Consumer Loans | 30-59 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 366 | 165 |
Consumer Loans | 60-89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,363 | 1,903 |
Consumer Loans | 60-89 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 63 | $ 60 |

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