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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 | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | $ 135,359 | $ 1,117,436
Year two | 1,138,128 | 1,320,936
Year three | 1,309,559 | 1,094,225
Year four | 1,059,734 | 503,703
Year five | 485,560 | 645,502
More than five years | 2,210,198 | 1,650,211
Revolving | 1,287,473 | 1,292,135
Revolving-Term | 30,023 | 29,193
Total | 7,656,034 | 7,653,341
Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 135,359 | 1,117,436
Year two | 1,138,128 | 1,320,560
Year three | 1,309,022 | 1,094,056
Year four | 1,059,691 | 502,950
Year five | 484,769 | 640,393
More than five years | 2,180,694 | 1,635,979
Revolving | 1,286,982 | 1,291,683
Revolving-Term | 28,180 | 27,337
Total | 7,622,825 | 7,630,394
Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 376
Year three | 537 | 169
Year four | 43 | 753
Year five | 791 | 5,109
More than five years | 29,504 | 14,232
Revolving | 491 | 452
Revolving-Term | 1,843 | 1,856
Total | 33,209 | 22,947
Commercial Loans | Commercial real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 25,970 | 276,677
Year two | 281,115 | 324,469
Year three | 351,226 | 439,308
Year four | 464,794 | 240,256
Year five | 228,899 | 419,371
More than five years | 1,313,640 | 926,636
Revolving | 34,138 | 32,418
Revolving-Term | 0 | 0
Total | 2,699,782 | 2,659,135
Commercial Loans | Commercial real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 25,970 | 276,677
Year two | 281,115 | 324,469
Year three | 351,226 | 439,308
Year four | 464,794 | 240,256
Year five | 228,899 | 419,371
More than five years | 1,296,487 | 920,316
Revolving | 34,138 | 32,418
Revolving-Term | 0 | 0
Total | 2,682,629 | 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 | 0 | 0
Year four | 0 | 0
Year five | 0 | 0
More than five years | 17,153 | 6,320
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 17,153 | 6,320
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 13,824 | 171,861
Year two | 174,698 | 231,978
Year three | 227,563 | 210,636
Year four | 188,869 | 54,696
Year five | 52,253 | 52,858
More than five years | 228,371 | 193,905
Revolving | 524,939 | 520,249
Revolving-Term | 0 | 0
Total | 1,410,517 | 1,436,183
Commercial Loans | Commercial and industrial | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 13,824 | 171,861
Year two | 174,698 | 231,978
Year three | 227,563 | 210,636
Year four | 188,869 | 54,696
Year five | 52,253 | 52,858
More than five years | 227,989 | 193,257
Revolving | 524,709 | 520,019
Revolving-Term | 0 | 0
Total | 1,409,905 | 1,435,305
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 | 0
More than five years | 382 | 648
Revolving | 230 | 230
Revolving-Term | 0 | 0
Total | 612 | 878
Commercial Loans | Commercial construction |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 13,086 | 75,596
Year two | 90,954 | 154,456
Year three | 141,982 | 82,313
Year four | 65,353 | 14,845
Year five | 14,758 | 4,727
More than five years | 9,008 | 4,438
Revolving | 12,234 | 14,208
Revolving-Term | 0 | 0
Total | 347,375 | 350,583
Commercial Loans | Commercial construction | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 13,086 | 75,596
Year two | 90,954 | 154,456
Year three | 141,982 | 82,313
Year four | 65,353 | 14,845
Year five | 14,758 | 151
More than five years | 4,048 | 4,054
Revolving | 12,234 | 14,208
Revolving-Term | 0 | 0
Total | 342,415 | 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 | 4,960 | 384
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | 4,960 | 4,960
Commercial Loans | Business banking |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 32,910 | 270,129
Year two | 254,296 | 262,606
Year three | 241,359 | 207,611
Year four | 190,039 | 88,018
Year five | 85,071 | 99,574
More than five years | 407,132 | 334,766
Revolving | 95,068 | 96,754
Revolving-Term | 1,280 | 1,307
Total | 1,307,155 | 1,360,765
Commercial Loans | Business banking | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 32,910 | 270,129
Year two | 254,296 | 262,606
Year three | 241,359 | 207,611
Year four | 190,039 | 87,979
Year five | 84,986 | 99,354
More than five years | 403,333 | 330,902
Revolving | 95,068 | 96,754
Revolving-Term | 1,257 | 1,283
Total | 1,303,248 | 1,356,618
Commercial Loans | Business banking | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 0
Year three | 0 | 0
Year four | 0 | 39
Year five | 85 | 220
More than five years | 3,799 | 3,864
Revolving | 0 | 0
Revolving-Term | 23 | 24
Total | 3,907 | 4,147
Consumer Loans | Consumer real estate |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 46,543 | 311,887
Year two | 327,577 | 335,462
Year three | 336,640 | 147,850
Year four | 145,121 | 102,041
Year five | 101,308 | 67,890
More than five years | 250,783 | 189,794
Revolving | 549,482 | 552,080
Revolving-Term | 25,519 | 24,774
Total | 1,782,973 | 1,731,778
Consumer Loans | Consumer real estate | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 46,543 | 311,887
Year two | 327,577 | 335,086
Year three | 336,103 | 147,689
Year four | 145,084 | 101,518
Year five | 100,671 | 67,577
More than five years | 247,704 | 186,909
Revolving | 549,221 | 551,858
Revolving-Term | 23,699 | 22,942
Total | 1,776,602 | 1,725,466
Consumer Loans | Consumer real estate | Nonaccrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 0 | 0
Year two | 0 | 376
Year three | 537 | 161
Year four | 37 | 523
Year five | 637 | 313
More than five years | 3,079 | 2,885
Revolving | 261 | 222
Revolving-Term | 1,820 | 1,832
Total | 6,371 | 6,312
Consumer Loans | Other consumer |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 3,026 | 11,286
Year two | 9,488 | 11,965
Year three | 10,789 | 6,507
Year four | 5,558 | 3,847
Year five | 3,271 | 1,082
More than five years | 1,264 | 672
Revolving | 71,612 | 76,426
Revolving-Term | 3,224 | 3,112
Total | 108,232 | 114,897
Consumer Loans | Other consumer | Accrual |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Current fiscal year | 3,026 | 11,286
Year two | 9,488 | 11,965
Year three | 10,789 | 6,499
Year four | 5,552 | 3,656
Year five | 3,202 | 1,082
More than five years | 1,133 | 541
Revolving | 71,612 | 76,426
Revolving-Term | 3,224 | 3,112
Total | 108,026 | 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 | 6 | 191
Year five | 69 | 0
More than five years | 131 | 131
Revolving | 0 | 0
Revolving-Term | 0 | 0
Total | $ 206 | $ 330

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