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Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Internally Assigned Risk Rating (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Total Loan Balance |  |  |
Current fiscal year | $ 298,890 |  | $ 893,015
Year two | 901,514 |  | 1,134,650
Year three | 1,087,612 |  | 1,191,528
Year four | 1,165,428 |  | 897,782
Year five | 876,014 |  | 421,743
More than five years | 2,188,191 |  | 1,885,462
Revolving | 1,282,043 |  | 1,284,808
Revolving-Term | 36,657 |  | 33,970
Total | 7,836,349 |  | 7,742,958
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 198 |  | 839
Year two | 0 |  | 191
Year three | 160 |  | 288
Year four | 231 |  | 1,338
Year five | 41 |  | 91
More than five years | 12 |  | 6,837
Revolving | 23 |  | 1,118
Revolving-Term | 219 |  | 1,486
Total | 884 | $ 6,939 | 12,188
Pass |  |  |
Total Loan Balance |  |  |
Current fiscal year | 298,890 |  | 892,431
Year two | 899,688 |  | 1,128,069
Year three | 1,074,112 |  | 1,171,403
Year four | 1,145,565 |  | 870,715
Year five | 849,546 |  | 417,507
More than five years | 2,083,653 |  | 1,775,175
Revolving | 1,239,095 |  | 1,243,868
Revolving-Term | 33,249 |  | 30,962
Total | 7,623,798 |  | 7,530,130
Special mention |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 1,259 |  | 2,020
Year three | 4,153 |  | 17,638
Year four | 16,103 |  | 2,112
Year five | 2,725 |  | 157
More than five years | 63,373 |  | 65,401
Revolving | 7,984 |  | 11,322
Revolving-Term | 264 |  | 268
Total | 95,861 |  | 98,918
Substandard |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 584
Year two | 567 |  | 4,561
Year three | 9,347 |  | 2,487
Year four | 3,760 |  | 24,589
Year five | 23,743 |  | 3,196
More than five years | 41,165 |  | 44,886
Revolving | 34,964 |  | 26,717
Revolving-Term | 3,144 |  | 2,740
Total | 116,690 |  | 109,760
Doubtful |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 0 |  | 366
Year five | 0 |  | 883
More than five years | 0 |  | 0
Revolving | 0 |  | 2,901
Revolving-Term | 0 |  | 0
Total | 0 |  | 4,150
Commercial Loans | Commercial real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 146,775 |  | 278,187
Year two | 270,301 |  | 289,081
Year three | 296,522 |  | 363,529
Year four | 351,124 |  | 415,621
Year five | 412,182 |  | 215,632
More than five years | 1,254,645 |  | 1,110,490
Revolving | 44,516 |  | 35,991
Revolving-Term | 0 |  | 0
Total | 2,776,065 |  | 2,708,531
Year-to-date Gross Charge-offs |  |  |
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 | 0 |  | 5,205
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 0 | 5,205 | 5,205
Commercial Loans | Commercial and industrial |  |  |
Total Loan Balance |  |  |
Current fiscal year | 27,389 |  | 120,143
Year two | 123,508 |  | 148,100
Year three | 136,108 |  | 195,756
Year four | 192,902 |  | 152,971
Year five | 145,744 |  | 31,312
More than five years | 209,881 |  | 197,426
Revolving | 495,559 |  | 505,929
Revolving-Term | 0 |  | 0
Total | 1,331,091 |  | 1,351,637
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 78
Year three | 0 |  | 0
Year four | 172 |  | 1,235
Year five | 0 |  | 0
More than five years | 0 |  | 91
Revolving | 0 |  | 1,032
Revolving-Term | 0 |  | 0
Total | 172 | 1,128 | 2,436
Commercial Loans | Commercial construction |  |  |
Total Loan Balance |  |  |
Current fiscal year | 36,944 |  | 119,355
Year two | 131,909 |  | 121,816
Year three | 104,310 |  | 73,851
Year four | 72,631 |  | 14,911
Year five | 13,054 |  | 884
More than five years | 2,111 |  | 2,139
Revolving | 6,910 |  | 8,310
Revolving-Term | 0 |  | 0
Total | 367,869 |  | 341,266
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 30 |  | 0
Year five | 0 |  | 0
More than five years | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 30 | 0 | 0
Commercial Loans | Business banking |  |  |
Total Loan Balance |  |  |
Current fiscal year | 46,684 |  | 149,624
Year two | 147,247 |  | 233,041
Year three | 225,252 |  | 226,654
Year four | 220,919 |  | 177,683
Year five | 172,626 |  | 76,643
More than five years | 404,821 |  | 345,327
Revolving | 95,875 |  | 92,981
Revolving-Term | 1,058 |  | 1,305
Total | 1,314,482 |  | 1,303,258
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 79
Year three | 106 |  | 124
Year four | 0 |  | 0
Year five | 34 |  | 56
More than five years | 3 |  | 1,486
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 143 | 98 | 1,745
Commercial Loans | Pass | Commercial real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 146,775 |  | 278,187
Year two | 270,301 |  | 287,081
Year three | 290,555 |  | 362,174
Year four | 349,795 |  | 413,781
Year five | 410,355 |  | 213,384
More than five years | 1,190,080 |  | 1,040,703
Revolving | 44,262 |  | 35,737
Revolving-Term | 0 |  | 0
Total | 2,702,123 |  | 2,631,047
Commercial Loans | Pass | Commercial and industrial |  |  |
Total Loan Balance |  |  |
Current fiscal year | 27,389 |  | 119,580
Year two | 122,961 |  | 147,007
Year three | 132,157 |  | 194,363
Year four | 192,211 |  | 131,877
Year five | 125,781 |  | 30,093
More than five years | 188,982 |  | 175,359
Revolving | 454,870 |  | 466,640
Revolving-Term | 0 |  | 0
Total | 1,244,351 |  | 1,264,919
Commercial Loans | Pass | Commercial construction |  |  |
Total Loan Balance |  |  |
Current fiscal year | 36,944 |  | 119,355
Year two | 131,040 |  | 121,816
Year three | 104,310 |  | 57,853
Year four | 56,662 |  | 14,911
Year five | 13,054 |  | 884
More than five years | 2,111 |  | 2,139
Revolving | 6,910 |  | 8,310
Revolving-Term | 0 |  | 0
Total | 351,031 |  | 325,268
Commercial Loans | Pass | Business banking |  |  |
Total Loan Balance |  |  |
Current fiscal year | 46,684 |  | 149,603
Year two | 146,837 |  | 230,784
Year three | 222,869 |  | 225,318
Year four | 219,286 |  | 173,763
Year five | 168,159 |  | 76,087
More than five years | 391,390 |  | 332,707
Revolving | 95,632 |  | 92,756
Revolving-Term | 354 |  | 597
Total | 1,291,211 |  | 1,281,615
Commercial Loans | Special mention | Commercial real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 2,000
Year three | 2,000 |  | 370
Year four | 350 |  | 1,840
Year five | 1,827 |  | 0
More than five years | 44,064 |  | 46,104
Revolving | 254 |  | 254
Revolving-Term | 0 |  | 0
Total | 48,495 |  | 50,568
Commercial Loans | Special mention | Commercial and industrial |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 20
Year three | 2,077 |  | 1,221
Year four | 691 |  | 142
Year five | 12 |  | 10
More than five years | 14,558 |  | 14,896
Revolving | 7,696 |  | 11,033
Revolving-Term | 0 |  | 0
Total | 25,034 |  | 27,322
Commercial Loans | Special mention | Commercial construction |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 869 |  | 0
Year three | 0 |  | 15,998
Year four | 14,963 |  | 0
Year five | 0 |  | 0
More than five years | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 15,832 |  | 15,998
Commercial Loans | Special mention | Business banking |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 390 |  | 0
Year three | 76 |  | 49
Year four | 99 |  | 130
Year five | 886 |  | 147
More than five years | 4,657 |  | 4,302
Revolving | 34 |  | 35
Revolving-Term | 264 |  | 268
Total | 6,406 |  | 4,931
Commercial Loans | Substandard | Commercial real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 3,967 |  | 985
Year four | 979 |  | 0
Year five | 0 |  | 1,834
More than five years | 20,501 |  | 23,683
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 25,447 |  | 26,502
Commercial Loans | Substandard | Commercial and industrial |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 563
Year two | 547 |  | 1,073
Year three | 1,874 |  | 172
Year four | 0 |  | 20,586
Year five | 19,951 |  | 740
More than five years | 6,341 |  | 7,171
Revolving | 32,993 |  | 25,355
Revolving-Term | 0 |  | 0
Total | 61,706 |  | 55,660
Commercial Loans | Substandard | Commercial construction |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 1,006 |  | 0
Year five | 0 |  | 0
More than five years | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 1,006 |  | 0
Commercial Loans | Substandard | Business banking |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 21
Year two | 20 |  | 2,257
Year three | 2,307 |  | 1,287
Year four | 1,534 |  | 3,790
Year five | 3,581 |  | 409
More than five years | 8,774 |  | 8,318
Revolving | 209 |  | 190
Revolving-Term | 440 |  | 440
Total | 16,865 |  | 16,712
Commercial Loans | Doubtful | Commercial real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 0 |  | 0
Year five | 0 |  | 414
More than five years | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 0 |  | 414
Commercial Loans | Doubtful | Commercial and industrial |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 0 |  | 366
Year five | 0 |  | 469
More than five years | 0 |  | 0
Revolving | 0 |  | 2,901
Revolving-Term | 0 |  | 0
Total | 0 |  | 3,736
Commercial Loans | Doubtful | Commercial construction |  |  |
Total Loan Balance |  |  |
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 | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 0 |  | 0
Commercial Loans | Doubtful | Business banking |  |  |
Total Loan Balance |  |  |
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 | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 0 |  | 0
Consumer Loans | Consumer real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 38,600 |  | 217,250
Year two | 221,466 |  | 335,763
Year three | 319,479 |  | 324,389
Year four | 321,530 |  | 133,347
Year five | 129,810 |  | 95,504
More than five years | 314,803 |  | 229,462
Revolving | 573,994 |  | 570,558
Revolving-Term | 28,995 |  | 27,236
Total | 1,948,677 |  | 1,933,509
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 38 |  | 0
Year four | 0 |  | 0
Year five | 0 |  | 9
More than five years | 5 |  | 37
Revolving | 23 |  | 86
Revolving-Term | 96 |  | 1,216
Total | 162 | 139 | 1,348
Consumer Loans | Other consumer |  |  |
Total Loan Balance |  |  |
Current fiscal year | 2,498 |  | 8,456
Year two | 7,083 |  | 6,849
Year three | 5,941 |  | 7,349
Year four | 6,322 |  | 3,249
Year five | 2,598 |  | 1,768
More than five years | 1,930 |  | 618
Revolving | 65,189 |  | 71,039
Revolving-Term | 6,604 |  | 5,429
Total | 98,165 |  | 104,757
Year-to-date Gross Charge-offs |  |  |
Current fiscal year | 198 |  | 839
Year two | 0 |  | 34
Year three | 16 |  | 164
Year four | 29 |  | 103
Year five | 7 |  | 26
More than five years | 4 |  | 18
Revolving | 0 |  | 0
Revolving-Term | 123 |  | 270
Total | 377 | $ 369 | 1,454
Consumer Loans | Pass | Consumer real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 38,600 |  | 217,250
Year two | 221,466 |  | 334,532
Year three | 318,280 |  | 324,346
Year four | 321,289 |  | 133,155
Year five | 129,619 |  | 95,301
More than five years | 309,314 |  | 223,799
Revolving | 572,232 |  | 569,386
Revolving-Term | 26,317 |  | 24,940
Total | 1,937,117 |  | 1,922,709
Consumer Loans | Pass | Other consumer |  |  |
Total Loan Balance |  |  |
Current fiscal year | 2,498 |  | 8,456
Year two | 7,083 |  | 6,849
Year three | 5,941 |  | 7,349
Year four | 6,322 |  | 3,228
Year five | 2,578 |  | 1,758
More than five years | 1,776 |  | 468
Revolving | 65,189 |  | 71,039
Revolving-Term | 6,578 |  | 5,425
Total | 97,965 |  | 104,572
Consumer Loans | Special mention | Consumer real estate |  |  |
Total Loan Balance |  |  |
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 | 94 |  | 99
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 94 |  | 99
Consumer Loans | Special mention | Other consumer |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 0 |  | 0
Year five | 0 |  |
More than five years | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term |  |  |
Total | 0 |  | 0
Consumer Loans | Substandard | Consumer real estate |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 1,231
Year three | 1,199 |  | 43
Year four | 241 |  | 192
Year five | 191 |  | 203
More than five years | 5,395 |  | 5,564
Revolving | 1,762 |  | 1,172
Revolving-Term | 2,678 |  | 2,296
Total | 11,466 |  | 10,701
Consumer Loans | Substandard | Other consumer |  |  |
Total Loan Balance |  |  |
Current fiscal year | 0 |  | 0
Year two | 0 |  | 0
Year three | 0 |  | 0
Year four | 0 |  | 21
Year five | 20 |  | 10
More than five years | 154 |  | 150
Revolving | 0 |  | 0
Revolving-Term | 26 |  | 4
Total | 200 |  | 185
Consumer Loans | Doubtful | Consumer real estate |  |  |
Total Loan Balance |  |  |
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 | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | 0 |  | 0
Consumer Loans | Doubtful | Other consumer |  |  |
Total Loan Balance |  |  |
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 | 0 |  | 0
Revolving | 0 |  | 0
Revolving-Term | 0 |  | 0
Total | $ 0 |  | $ 0

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