Allowance for Credit Losses and Credit Quality of Loans, Past Due Loans (Details) $ in Thousands	3 Months Ended
Mar. 31, 2025 USD ($) Relationship	Dec. 31, 2024 USD ($) Relationship
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	3	3
Individually evaluated loans, amortized cost	$ 26,700	$ 28,800
Individually evaluated loans, allowance for credit losses	0	0
Individually evaluated loans, decrease in amortized cost by partially charge-offs	$ 2,100
Individually evaluated loans, number of new relationships \| Relationship	1
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	$ 44,829	45,819
Recorded total loans	9,980,267	9,969,910
Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	32,097	33,532
31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	24,010	21,601
61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	5,225	6,133
Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	2,862	5,798
Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	9,903,341	9,890,559
C&I [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,437,696	1,430,213
CRE [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	3,704,143	3,696,140
Auto [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,281,896	1,244,906
Residential Solar [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	800,090	820,079
Other Consumer [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	100,301	109,217
Commercial Loans [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	30,586	32,144
Recorded total loans	5,141,839	5,126,353
Commercial Loans [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	6,366	1,739
Commercial Loans [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	5,209	1,096
Commercial Loans [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	467	643
Commercial Loans [Member] \| Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	690	0
Commercial Loans [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	5,104,887	5,092,470
Commercial Loans [Member] \| C&I [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	2,261	2,116
Recorded total loans	1,437,696	1,430,213
Commercial Loans [Member] \| C&I [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,160	850
Commercial Loans [Member] \| C&I [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,015	398
Commercial Loans [Member] \| C&I [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	145	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	1,434,275	1,427,247
Commercial Loans [Member] \| CRE [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	28,325	30,028
Recorded total loans	3,704,143	3,696,140
Commercial Loans [Member] \| CRE [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	5,206	889
Commercial Loans [Member] \| CRE [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	4,194	698
Commercial Loans [Member] \| CRE [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	322	191
Commercial Loans [Member] \| CRE [Member] \| Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	690	0
Commercial Loans [Member] \| CRE [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	3,670,612	3,665,223
Consumer Loans [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	2,270	2,529
Recorded total loans	2,182,287	2,174,202
Consumer Loans [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	21,170	25,555
Consumer Loans [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	15,068	17,145
Consumer Loans [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	4,196	5,023
Consumer Loans [Member] \| Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,906	3,387
Consumer Loans [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	2,158,847	2,146,118
Consumer Loans [Member] \| Auto [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	1,925	2,054
Recorded total loans	1,281,896	1,244,906
Consumer Loans [Member] \| Auto [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	12,613	14,474
Consumer Loans [Member] \| Auto [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	9,863	11,527
Consumer Loans [Member] \| Auto [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,778	2,047
Consumer Loans [Member] \| Auto [Member] \| Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	972	900
Consumer Loans [Member] \| Auto [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,267,358	1,228,378
Consumer Loans [Member] \| Residential Solar [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	127	212
Recorded total loans	800,090	820,079
Consumer Loans [Member] \| Residential Solar [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	6,068	7,656
Consumer Loans [Member] \| Residential Solar [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	3,780	4,066
Consumer Loans [Member] \| Residential Solar [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,735	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	553	1,599
Consumer Loans [Member] \| Residential Solar [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	793,895	812,211
Consumer Loans [Member] \| Other Consumer [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	218	263
Recorded total loans	100,301	109,217
Consumer Loans [Member] \| Other Consumer [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	2,489	3,425
Consumer Loans [Member] \| Other Consumer [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	1,425	1,552
Consumer Loans [Member] \| Other Consumer [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	683	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	97,594	105,529
Residential [Member]
Past Due and Nonperforming Loans [Abstract]
Nonaccrual	11,973	11,146
Recorded total loans	2,656,141	2,669,355
Residential [Member] \| Past Due [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	4,561	6,238
Residential [Member] \| 31-60 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	3,733	3,360
Residential [Member] \| 61-90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	562	467
Residential [Member] \| Greater Than 90 Days Past Due Accruing [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	266	2,411
Residential [Member] \| Current [Member]
Past Due and Nonperforming Loans [Abstract]
Recorded total loans	$ 2,639,607	$ 2,651,971

The number of new relationships of financing receivables that were individually evaluated for impairment.

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The number of relationships of financing receivables that were individually evaluated for impairment.

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The threshold balance for financing receivables that are specifically evaluated for individual credit loss.

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Amount of valuation allowance for loans and leases receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of charge-off of loans and leases receivable that partially offset the increase in amortized cost basis.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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