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Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 532,634 | $ 1,117,436
Year two | 1,165,227 | 1,320,936
Year three | 1,263,568 | 1,094,225
Year four | 942,600 | 503,703
Year five | 451,252 | 645,502
More than five years | 2,036,020 | 1,650,211
Revolving | 1,263,917 | 1,292,135
Revolving-Term | 33,836 | 29,193
Total | 7,689,054 | 7,653,341
Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 532,634 | 1,117,436
Year two | 1,164,529 | 1,320,560
Year three | 1,262,354 | 1,094,056
Year four | 942,496 | 502,950
Year five | 450,303 | 640,393
More than five years | 2,012,919 | 1,635,979
Revolving | 1,259,745 | 1,291,683
Revolving-Term | 32,185 | 27,337
Total | 7,657,165 | 7,630,394
Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 698 | 376
Year three | 1,214 | 169
Year four | 104 | 753
Year five | 949 | 5,109
More than five years | 23,101 | 14,232
Revolving | 4,172 | 452
Revolving-Term | 1,651 | 1,856
Total | 31,889 | 22,947
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 122,012 | 276,677
Year two | 287,445 | 324,469
Year three | 369,944 | 439,308
Year four | 412,477 | 240,256
Year five | 218,149 | 419,371
More than five years | 1,217,037 | 926,636
Revolving | 33,752 | 32,418
Revolving-Term | 0 | 0
Total | 2,660,816 | 2,659,135
Commercial Loans | Commercial real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 122,012 | 276,677
Year two | 287,445 | 324,469
Year three | 368,955 | 439,308
Year four | 412,477 | 240,256
Year five | 218,149 | 419,371
More than five years | 1,203,855 | 920,316
Revolving | 33,752 | 32,418
Revolving-Term | 0 | 0
Total | 2,646,645 | 2,652,815
Commercial Loans | Commercial real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 989 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 13,182 | 6,320
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 14,171 | 6,320
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 61,621 | 171,861
Year two | 168,934 | 231,978
Year three | 217,452 | 210,636
Year four | 162,667 | 54,696
Year five | 42,312 | 52,858
More than five years | 206,647 | 193,905
Revolving | 503,844 | 520,249
Revolving-Term | 0 | 0
Total | 1,363,477 | 1,436,183
Commercial Loans | Commercial and industrial | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 61,621 | 171,861
Year two | 168,895 | 231,978
Year three | 217,452 | 210,636
Year four | 162,567 | 54,696
Year five | 42,312 | 52,858
More than five years | 206,647 | 193,257
Revolving | 500,681 | 520,019
Revolving-Term | 0 | 0
Total | 1,360,175 | 1,435,305
Commercial Loans | Commercial and industrial | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 39 | 0
Year three | 0 | 0
Year four | 100 | 0
Year five | 0 | 0
More than five years | 0 | 648
Revolving | 3,163 | 230
Revolving-Term | 0 | 0
Total | 3,302 | 878
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 70,752 | 75,596
Year two | 116,904 | 154,456
Year three | 115,703 | 82,313
Year four | 44,394 | 14,845
Year five | 12,579 | 4,727
More than five years | 6,274 | 4,438
Revolving | 7,693 | 14,208
Revolving-Term | 0 | 0
Total | 374,299 | 350,583
Commercial Loans | Commercial construction | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 70,752 | 75,596
Year two | 116,904 | 154,456
Year three | 115,703 | 82,313
Year four | 44,394 | 14,845
Year five | 12,579 | 151
More than five years | 2,858 | 4,054
Revolving | 7,693 | 14,208
Revolving-Term | 0 | 0
Total | 370,883 | 345,623
Commercial Loans | Commercial construction | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 0
Year five | 0 | 4,576
More than five years | 3,416 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 3,416 | 4,960
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 103,628 | 270,129
Year two | 244,309 | 262,606
Year three | 225,878 | 207,611
Year four | 179,543 | 88,018
Year five | 78,867 | 99,574
More than five years | 369,124 | 334,766
Revolving | 88,495 | 96,754
Revolving-Term | 1,236 | 1,307
Total | 1,291,080 | 1,360,765
Commercial Loans | Business banking | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 103,628 | 270,129
Year two | 244,123 | 262,606
Year three | 225,653 | 207,611
Year four | 179,543 | 87,979
Year five | 78,694 | 99,354
More than five years | 365,840 | 330,902
Revolving | 88,495 | 96,754
Revolving-Term | 1,201 | 1,283
Total | 1,287,177 | 1,356,618
Commercial Loans | Business banking | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 186 | 0
Year three | 225 | 0
Year four | 0 | 39
Year five | 173 | 220
More than five years | 3,284 | 3,864
Revolving | 0 | 0
Revolving-Term | 35 | 24
Total | 3,903 | 4,147
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 167,541 | 311,887
Year two | 339,911 | 335,462
Year three | 326,286 | 147,850
Year four | 139,497 | 102,041
Year five | 97,115 | 67,890
More than five years | 236,193 | 189,794
Revolving | 560,726 | 552,080
Revolving-Term | 26,878 | 24,774
Total | 1,894,147 | 1,731,778
Consumer Loans | Consumer real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 167,541 | 311,887
Year two | 339,438 | 335,086
Year three | 326,286 | 147,689
Year four | 139,497 | 101,518
Year five | 96,453 | 67,577
More than five years | 233,120 | 186,909
Revolving | 559,717 | 551,858
Revolving-Term | 25,262 | 22,942
Total | 1,887,314 | 1,725,466
Consumer Loans | Consumer real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 473 | 376
Year three | 0 | 161
Year four | 0 | 523
Year five | 662 | 313
More than five years | 3,073 | 2,885
Revolving | 1,009 | 222
Revolving-Term | 1,616 | 1,832
Total | 6,833 | 6,312
Consumer Loans | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 7,080 | 11,286
Year two | 7,724 | 11,965
Year three | 8,305 | 6,507
Year four | 4,022 | 3,847
Year five | 2,230 | 1,082
More than five years | 745 | 672
Revolving | 69,407 | 76,426
Revolving-Term | 5,722 | 3,112
Total | 105,235 | 114,897
Consumer Loans | Other consumer | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 7,080 | 11,286
Year two | 7,724 | 11,965
Year three | 8,305 | 6,499
Year four | 4,018 | 3,656
Year five | 2,116 | 1,082
More than five years | 599 | 541
Revolving | 69,407 | 76,426
Revolving-Term | 5,722 | 3,112
Total | 104,971 | 114,567
Consumer Loans | Other consumer | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 8
Year four | 4 | 191
Year five | 114 | 0
More than five years | 146 | 131
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 264 | $ 330

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