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Allowance for Credit Losses and Credit Quality of Loans, Past Due Loans (Details) $ in Thousands | Sep. 30, 2025 USD ($) Relationship | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) Relationship
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Allowance for Credit Losses and Credit Quality of Loans [Abstract] |  |  |
Threshold balance for loans specifically evaluated for individual credit loss | $ 1,000 |  |
Individually evaluated loans, number of relationships | Relationship | 7 |  | 3
Individually evaluated loans, number of new relationships | Relationship | 6 |  |
Individually evaluated loans, amortized cost | $ 16,000 | $ 13,900 | $ 28,800
Individually evaluated loans, allowance for credit losses | 0 |  | 0
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 46,450 |  | 45,819
Recorded total loans | 11,595,134 |  | 9,969,910
Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 44,328 |  | 33,532
31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 32,050 |  | 21,601
61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 5,312 |  | 6,133
Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 6,966 |  | 5,798
Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 11,504,356 |  | 9,890,559
C&I [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,619,228 |  | 1,430,213
CRE [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 4,659,122 |  | 3,696,140
Auto [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,303,636 |  | 1,244,906
Residential Solar [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 757,982 |  | 820,079
Other Consumer [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 88,273 |  | 109,217
Commercial Loans [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 21,393 |  | 32,144
Recorded total loans | 6,278,350 |  | 5,126,353
Commercial Loans [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 12,685 |  | 1,739
Commercial Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 9,449 |  | 1,096
Commercial Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,137 |  | 643
Commercial Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,099 |  | 0
Commercial Loans [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 6,244,272 |  | 5,092,470
Commercial Loans [Member] | C&I [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 1,871 |  | 2,116
Recorded total loans | 1,619,228 |  | 1,430,213
Commercial Loans [Member] | C&I [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,701 |  | 850
Commercial Loans [Member] | C&I [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,567 |  | 398
Commercial Loans [Member] | C&I [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,134 |  | 452
Commercial Loans [Member] | C&I [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 0 |  | 0
Commercial Loans [Member] | C&I [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,614,656 |  | 1,427,247
Commercial Loans [Member] | CRE [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 19,522 |  | 30,028
Recorded total loans | 4,659,122 |  | 3,696,140
Commercial Loans [Member] | CRE [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 9,984 |  | 889
Commercial Loans [Member] | CRE [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 7,882 |  | 698
Commercial Loans [Member] | CRE [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 3 |  | 191
Commercial Loans [Member] | CRE [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,099 |  | 0
Commercial Loans [Member] | CRE [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 4,629,616 |  | 3,665,223
Consumer Loans [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 2,639 |  | 2,529
Recorded total loans | 2,149,891 |  | 2,174,202
Consumer Loans [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 21,942 |  | 25,555
Consumer Loans [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 16,175 |  | 17,145
Consumer Loans [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 3,423 |  | 5,023
Consumer Loans [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,344 |  | 3,387
Consumer Loans [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,125,310 |  | 2,146,118
Consumer Loans [Member] | Auto [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 2,272 |  | 2,054
Recorded total loans | 1,303,636 |  | 1,244,906
Consumer Loans [Member] | Auto [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 13,895 |  | 14,474
Consumer Loans [Member] | Auto [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 11,293 |  | 11,527
Consumer Loans [Member] | Auto [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,732 |  | 2,047
Consumer Loans [Member] | Auto [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 870 |  | 900
Consumer Loans [Member] | Auto [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,287,469 |  | 1,228,378
Consumer Loans [Member] | Residential Solar [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 195 |  | 212
Recorded total loans | 757,982 |  | 820,079
Consumer Loans [Member] | Residential Solar [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 6,006 |  | 7,656
Consumer Loans [Member] | Residential Solar [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 3,717 |  | 4,066
Consumer Loans [Member] | Residential Solar [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,196 |  | 1,991
Consumer Loans [Member] | Residential Solar [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,093 |  | 1,599
Consumer Loans [Member] | Residential Solar [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 751,781 |  | 812,211
Consumer Loans [Member] | Other Consumer [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 172 |  | 263
Recorded total loans | 88,273 |  | 109,217
Consumer Loans [Member] | Other Consumer [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,041 |  | 3,425
Consumer Loans [Member] | Other Consumer [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 1,165 |  | 1,552
Consumer Loans [Member] | Other Consumer [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 495 |  | 985
Consumer Loans [Member] | Other Consumer [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 381 |  | 888
Consumer Loans [Member] | Other Consumer [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 86,060 |  | 105,529
Residential [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Nonaccrual | 22,418 |  | 11,146
Recorded total loans | 3,166,893 |  | 2,669,355
Residential [Member] | Past Due [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 9,701 |  | 6,238
Residential [Member] | 31-60 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 6,426 |  | 3,360
Residential [Member] | 61-90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 752 |  | 467
Residential [Member] | Greater Than 90 Days Past Due Accruing [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | 2,523 |  | 2,411
Residential [Member] | Current [Member] |  |  |
Past Due and Nonperforming Loans [Abstract] |  |  |
Recorded total loans | $ 3,134,774 |  | $ 2,651,971

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