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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, 2023 | Dec. 31, 2022
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 875,940 | $ 1,271,764
Year two | 1,301,309 | 1,214,107
Year three | 1,118,263 | 586,544
Year four | 513,435 | 725,517
Year five | 668,747 | 449,759
More than five years | 1,712,993 | 1,528,088
Revolving | 1,295,848 | 1,381,517
Revolving-Term | 29,383 | 26,673
Total | 7,515,918 | 7,183,969
Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 875,940 | 1,271,764
Year two | 1,300,933 | 1,213,905
Year three | 1,118,219 | 585,892
Year four | 513,157 | 724,629
Year five | 667,958 | 448,121
More than five years | 1,704,170 | 1,513,912
Revolving | 1,295,410 | 1,380,980
Revolving-Term | 27,454 | 25,714
Total | 7,503,241 | 7,164,917
Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 376 | 202
Year three | 44 | 652
Year four | 278 | 888
Year five | 789 | 1,638
More than five years | 8,823 | 14,176
Revolving | 438 | 537
Revolving-Term | 1,929 | 959
Total | 12,677 | 19,052
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 221,775 | 292,732
Year two | 268,261 | 360,423
Year three | 422,345 | 269,049
Year four | 245,339 | 449,493
Year five | 426,370 | 261,941
More than five years | 971,630 | 883,535
Revolving | 35,469 | 21,666
Revolving-Term | 0 | 0
Total | 2,591,189 | 2,538,839
Commercial Loans | Commercial real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 221,775 | 292,732
Year two | 268,261 | 360,423
Year three | 422,345 | 269,049
Year four | 245,339 | 449,493
Year five | 426,370 | 261,941
More than five years | 970,368 | 876,435
Revolving | 35,469 | 21,666
Revolving-Term | 0 | 0
Total | 2,589,927 | 2,531,739
Commercial Loans | Commercial real estate | 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 | 0
More than five years | 1,262 | 7,100
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 1,262 | 7,100
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 143,170 | 253,696
Year two | 235,058 | 289,448
Year three | 224,893 | 88,544
Year four | 58,238 | 73,998
Year five | 59,273 | 65,911
More than five years | 184,340 | 147,273
Revolving | 519,169 | 591,522
Revolving-Term | 0 | 0
Total | 1,424,141 | 1,510,392
Commercial Loans | Commercial and industrial | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 143,170 | 253,696
Year two | 235,058 | 289,448
Year three | 224,893 | 88,544
Year four | 58,238 | 73,998
Year five | 59,273 | 65,858
More than five years | 183,651 | 147,273
Revolving | 518,939 | 591,292
Revolving-Term | 0 | 0
Total | 1,423,222 | 1,510,109
Commercial Loans | Commercial and industrial | 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 | 53
More than five years | 689 | 0
Revolving | 230 | 230
Revolving-Term | 0 | 0
Total | 919 | 283
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 44,519 | 120,655
Year two | 188,037 | 170,691
Year three | 97,525 | 40,762
Year four | 13,266 | 14,442
Year five | 10,815 | 3,953
More than five years | 6,202 | 4,176
Revolving | 12,475 | 27,284
Revolving-Term | 0 | 0
Total | 372,839 | 381,963
Commercial Loans | Commercial construction | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 44,519 | 120,655
Year two | 188,037 | 170,691
Year three | 97,525 | 40,762
Year four | 13,266 | 14,442
Year five | 10,815 | 3,953
More than five years | 5,818 | 3,792
Revolving | 12,475 | 27,284
Revolving-Term | 0 | 0
Total | 372,455 | 381,579
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 | 0
More than five years | 384 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 384 | 384
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 230,663 | 287,679
Year two | 270,110 | 233,723
Year three | 216,729 | 91,149
Year four | 91,167 | 109,731
Year five | 102,761 | 84,889
More than five years | 351,469 | 292,211
Revolving | 98,585 | 105,271
Revolving-Term | 1,830 | 1,291
Total | 1,363,314 | 1,205,944
Commercial Loans | Business banking | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 230,663 | 287,679
Year two | 270,110 | 233,656
Year three | 216,729 | 91,149
Year four | 91,128 | 109,479
Year five | 102,469 | 83,689
More than five years | 347,909 | 289,435
Revolving | 98,585 | 105,172
Revolving-Term | 1,711 | 1,195
Total | 1,359,304 | 1,201,454
Commercial Loans | Business banking | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 67
Year three | 0 | 0
Year four | 39 | 252
Year five | 292 | 1,200
More than five years | 3,560 | 2,776
Revolving | 0 | 99
Revolving-Term | 119 | 96
Total | 4,010 | 4,490
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 225,529 | 296,948
Year two | 326,707 | 149,003
Year three | 149,242 | 91,613
Year four | 101,938 | 74,583
Year five | 67,984 | 32,031
More than five years | 198,475 | 200,169
Revolving | 554,347 | 553,649
Revolving-Term | 24,834 | 23,957
Total | 1,649,056 | 1,421,953
Consumer Loans | Consumer real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 225,529 | 296,948
Year two | 326,331 | 148,868
Year three | 149,205 | 91,085
Year four | 101,895 | 73,947
Year five | 67,487 | 31,646
More than five years | 195,678 | 196,384
Revolving | 554,139 | 553,441
Revolving-Term | 23,024 | 23,108
Total | 1,643,288 | 1,415,427
Consumer Loans | Consumer real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 376 | 135
Year three | 37 | 528
Year four | 43 | 636
Year five | 497 | 385
More than five years | 2,797 | 3,785
Revolving | 208 | 208
Revolving-Term | 1,810 | 849
Total | 5,768 | 6,526
Consumer Loans | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 10,284 | 20,054
Year two | 13,136 | 10,819
Year three | 7,529 | 5,427
Year four | 3,487 | 3,270
Year five | 1,544 | 1,034
More than five years | 877 | 724
Revolving | 75,803 | 82,125
Revolving-Term | 2,719 | 1,425
Total | 115,379 | 124,878
Consumer Loans | Other consumer | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 10,284 | 20,054
Year two | 13,136 | 10,819
Year three | 7,522 | 5,303
Year four | 3,291 | 3,270
Year five | 1,544 | 1,034
More than five years | 746 | 593
Revolving | 75,803 | 82,125
Revolving-Term | 2,719 | 1,411
Total | 115,045 | 124,609
Consumer Loans | Other consumer | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 7 | 124
Year four | 196 | 0
Year five | 0 | 0
More than five years | 131 | 131
Revolving | 0 | 0
Revolving-Term | 0 | 14
Total | $ 334 | $ 269

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