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Allowance for Credit Losses and Credit Quality of Loans, Credit Quality Indicators (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Minimum number of days past due for loans to be considered nonperforming | 90 days |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | $ 364,006 | $ 1,444,621
2023/2022 | 1,436,145 | 1,989,711
2022/2021 | 1,864,247 | 1,688,309
2021/2020 | 1,610,531 | 1,019,863
2020/2019 | 996,330 | 692,961
Prior | 2,407,804 | 1,840,266
Revolving Loans Amortized Cost Basis | 937,568 | 920,868
Revolving Loans Converted to Term | 71,446 | 54,114
Total | 9,688,077 | 9,650,713
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | (1,161)
2023/2022 | (586) | (9,878)
2022/2021 | (3,114) | (9,586)
2021/2020 | (1,815) | (1,830)
2020/2019 | (376) | (1,805)
Prior | (789) | (2,518)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (6,680) | (26,778)
C&I [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 60,820 | 231,165
2023/2022 | 219,735 | 274,930
2022/2021 | 249,576 | 243,881
2021/2020 | 233,859 | 161,857
2020/2019 | 150,543 | 76,826
Prior | 137,971 | 71,313
Revolving Loans Amortized Cost Basis | 348,904 | 333,003
Revolving Loans Converted to Term | 2,963 | 4,530
Total | 1,404,371 | 1,397,505
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | (24)
2023/2022 | (9) | (3,021)
2022/2021 | (900) | (5)
2021/2020 | 0 | (86)
2020/2019 | 0 | 0
Prior | (76) | (600)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (985) | (3,736)
C&I [Member] | Pass [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 60,820 | 229,249
2023/2022 | 214,985 | 270,796
2022/2021 | 243,619 | 241,993
2021/2020 | 231,577 | 158,051
2020/2019 | 146,409 | 74,469
Prior | 129,310 | 63,826
Revolving Loans Amortized Cost Basis | 318,078 | 299,248
Revolving Loans Converted to Term | 2,585 | 2,923
Total | 1,347,383 | 1,340,555
C&I [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 420
2023/2022 | 1,795 | 1,672
2022/2021 | 2,802 | 277
2021/2020 | 378 | 3,524
2020/2019 | 3,845 | 87
Prior | 1,812 | 1,854
Revolving Loans Amortized Cost Basis | 15,946 | 19,489
Revolving Loans Converted to Term | 251 | 0
Total | 26,829 | 27,323
C&I [Member] | Substandard [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 1,496
2023/2022 | 2,934 | 2,461
2022/2021 | 3,154 | 1,609
2021/2020 | 1,885 | 282
2020/2019 | 289 | 2,266
Prior | 6,845 | 5,632
Revolving Loans Amortized Cost Basis | 14,880 | 14,266
Revolving Loans Converted to Term | 127 | 1,607
Total | 30,114 | 29,619
C&I [Member] | Doubtful [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 0
2023/2022 | 21 | 1
2022/2021 | 1 | 2
2021/2020 | 19 | 0
2020/2019 | 0 | 4
Prior | 4 | 1
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 45 | 8
CRE [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 81,048 | 357,108
2023/2022 | 366,262 | 523,404
2022/2021 | 499,358 | 594,415
2021/2020 | 572,590 | 460,311
2020/2019 | 454,540 | 340,767
Prior | 1,103,458 | 816,067
Revolving Loans Amortized Cost Basis | 314,066 | 307,971
Revolving Loans Converted to Term | 54,224 | 33,705
Total | 3,445,546 | 3,433,748
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 0
2023/2022 | 0 | 0
2022/2021 | 0 | 0
2021/2020 | 0 | 0
2020/2019 | 0 | (114)
Prior | 0 | (304)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 0 | (418)
CRE [Member] | Pass [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 81,048 | 353,161
2023/2022 | 362,660 | 518,201
2022/2021 | 492,661 | 561,897
2021/2020 | 546,787 | 452,110
2020/2019 | 449,533 | 327,804
Prior | 1,013,118 | 739,189
Revolving Loans Amortized Cost Basis | 308,977 | 294,039
Revolving Loans Converted to Term | 37,243 | 33,705
Total | 3,292,027 | 3,280,106
CRE [Member] | Special Mention [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 3,577
2023/2022 | 3,602 | 4,472
2022/2021 | 5,971 | 10,711
2021/2020 | 7,842 | 7,055
2020/2019 | 3,875 | 9,967
Prior | 28,841 | 39,460
Revolving Loans Amortized Cost Basis | 3,547 | 2,970
Revolving Loans Converted to Term | 0 | 0
Total | 53,678 | 78,212
CRE [Member] | Substandard [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 370
2023/2022 | 0 | 731
2022/2021 | 726 | 21,807
2021/2020 | 17,961 | 1,146
2020/2019 | 1,132 | 2,996
Prior | 61,499 | 37,418
Revolving Loans Amortized Cost Basis | 1,542 | 10,962
Revolving Loans Converted to Term | 16,981 | 0
Total | 99,841 | 75,430
Auto [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 175,480 | 474,901
2023/2022 | 431,015 | 364,757
2022/2021 | 332,373 | 158,081
2021/2020 | 139,639 | 42,834
2020/2019 | 36,234 | 45,712
Prior | 43,332 | 13,145
Revolving Loans Amortized Cost Basis | 0 | 12
Revolving Loans Converted to Term | 0 | 0
Total | 1,158,073 | 1,099,442
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | (102)
2023/2022 | (274) | (1,183)
2022/2021 | (493) | (1,066)
2021/2020 | (226) | (340)
2020/2019 | (12) | (301)
Prior | (122) | (295)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (1,127) | (3,287)
Auto [Member] | Performing [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 175,451 | 474,369
2023/2022 | 430,001 | 363,516
2022/2021 | 331,202 | 157,251
2021/2020 | 138,915 | 42,644
2020/2019 | 36,140 | 45,406
Prior | 43,045 | 13,071
Revolving Loans Amortized Cost Basis | 0 | 12
Revolving Loans Converted to Term | 0 | 0
Total | 1,154,754 | 1,096,269
Auto [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 29 | 532
2023/2022 | 1,014 | 1,241
2022/2021 | 1,171 | 830
2021/2020 | 724 | 190
2020/2019 | 94 | 306
Prior | 287 | 74
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 3,319 | 3,173
Residential Solar [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 1,365 | 155,425
2023/2022 | 149,789 | 431,692
2022/2021 | 422,854 | 179,044
2021/2020 | 176,234 | 65,400
2020/2019 | 63,222 | 46,601
Prior | 82,683 | 39,593
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 896,147 | 917,755
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | (150)
2023/2022 | (53) | (1,930)
2022/2021 | (910) | (923)
2021/2020 | (136) | (45)
2020/2019 | 0 | (558)
Prior | (196) | (345)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (1,295) | (3,951)
Residential Solar [Member] | Performing [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 1,365 | 155,425
2023/2022 | 149,789 | 430,855
2022/2021 | 422,422 | 178,839
2021/2020 | 176,158 | 65,382
2020/2019 | 63,222 | 46,554
Prior | 82,620 | 39,540
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 895,576 | 916,595
Residential Solar [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 0
2023/2022 | 0 | 837
2022/2021 | 432 | 205
2021/2020 | 76 | 18
2020/2019 | 0 | 47
Prior | 63 | 53
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | 571 | 1,160
Other Consumer [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Overdrawn deposit related to gross charge-offs reported as 2022 originations |  | 200
Overdrawn deposit related to gross charge-offs reported as 2023 originations | 200 | 800
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 5,600 | 13,089
2023/2022 | 10,564 | 27,638
2022/2021 | 22,904 | 58,561
2021/2020 | 48,597 | 21,231
2020/2019 | 18,068 | 14,604
Prior | 25,976 | 16,125
Revolving Loans Amortized Cost Basis | 19,016 | 19,046
Revolving Loans Converted to Term | 40 | 66
Total | 150,765 | 170,360
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | (885)
2023/2022 | (250) | (3,744)
2022/2021 | (811) | (7,511)
2021/2020 | (1,453) | (1,329)
2020/2019 | (364) | (832)
Prior | (281) | (568)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (3,159) | (14,869)
Other Consumer [Member] | Performing [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 5,600 | 13,089
2023/2022 | 10,559 | 27,394
2022/2021 | 22,720 | 57,876
2021/2020 | 47,947 | 21,087
2020/2019 | 18,029 | 14,548
Prior | 25,681 | 15,964
Revolving Loans Amortized Cost Basis | 19,015 | 19,042
Revolving Loans Converted to Term | 33 | 21
Total | 149,584 | 169,021
Other Consumer [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 0
2023/2022 | 5 | 244
2022/2021 | 184 | 685
2021/2020 | 650 | 144
2020/2019 | 39 | 56
Prior | 295 | 161
Revolving Loans Amortized Cost Basis | 1 | 4
Revolving Loans Converted to Term | 7 | 45
Total | 1,181 | 1,339
Residential [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 39,693 | 212,933
2023/2022 | 258,780 | 367,290
2022/2021 | 337,182 | 454,327
2021/2020 | 439,612 | 268,230
2020/2019 | 273,723 | 168,451
Prior | 1,014,384 | 884,023
Revolving Loans Amortized Cost Basis | 255,582 | 260,836
Revolving Loans Converted to Term | 14,219 | 15,813
Total | 2,633,175 | 2,631,903
Gross Charge-offs by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 0
2023/2022 | 0 | 0
2022/2021 | 0 | (81)
2021/2020 | 0 | (30)
2020/2019 | 0 | 0
Prior | (114) | (406)
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 0
Total | (114) | (517)
Residential [Member] | Performing [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 39,693 | 212,799
2023/2022 | 258,154 | 366,860
2022/2021 | 336,357 | 453,206
2021/2020 | 438,007 | 267,845
2020/2019 | 273,451 | 167,860
Prior | 1,006,816 | 876,563
Revolving Loans Amortized Cost Basis | 255,582 | 260,836
Revolving Loans Converted to Term | 14,219 | 15,300
Total | 2,622,279 | 2,621,269
Residential [Member] | Nonperforming [Member] |  |
Credit Quality by Loan Class by Vintage [Abstract] |  |
2024/2023 | 0 | 134
2023/2022 | 626 | 430
2022/2021 | 825 | 1,121
2021/2020 | 1,605 | 385
2020/2019 | 272 | 591
Prior | 7,568 | 7,460
Revolving Loans Amortized Cost Basis | 0 | 0
Revolving Loans Converted to Term | 0 | 513
Total | $ 10,896 | $ 10,634

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