Loans, Allowance for Credit Losses, and Asset Quality Information - Schedule of Analysis of Payment Status of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Loans	$ 8,988,748	$ 8,722,419
Nonaccrual loans	44,283	36,315
Allowance for credit loss, fee, and loan in process	8,989,553	8,721,682
Unamortized net deferred loan (fees)/costs	(805)	737
Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	8,933,977	8,666,876
Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	8,655	13,101
Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	2,638	5,390
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	8,697	9,130
Allowance for credit loss, fee, and loan in process	1,014,295	1,046,438
Commercial and industrial \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	1,003,760	1,034,943
Commercial and industrial \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	864	1,824
Commercial and industrial \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	974	541
Commercial and industrial \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	1,014,295	1,046,438
Real estate, commercial \| Construction, development & other land loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	303	202
Allowance for credit loss, fee, and loan in process	847,912	753,199
Real estate, commercial \| Construction, development & other land loans \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	847,574	752,388
Real estate, commercial \| Construction, development & other land loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	35	602
Real estate, commercial \| Construction, development & other land loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	7
Real estate, commercial \| Construction, development & other land loans \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	847,912	753,199
Real estate, commercial \| Commercial real estate - owner occupied
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	14,264	13,464
Allowance for credit loss, fee, and loan in process	1,358,100	1,353,912
Real estate, commercial \| Commercial real estate - owner occupied \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	1,343,327	1,338,042
Real estate, commercial \| Commercial real estate - owner occupied \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	509	2,130
Real estate, commercial \| Commercial real estate - owner occupied \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	276
Real estate, commercial \| Commercial real estate - owner occupied \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	1,358,100	1,353,912
Real estate, commercial \| Commercial real estate - non owner occupied
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	8,518	4,978
Allowance for credit loss, fee, and loan in process	2,974,749	2,843,555
Real estate, commercial \| Commercial real estate - non owner occupied \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	2,966,082	2,838,054
Real estate, commercial \| Commercial real estate - non owner occupied \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	102	0
Real estate, commercial \| Commercial real estate - non owner occupied \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	47	523
Real estate, commercial \| Commercial real estate - non owner occupied \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	2,974,749	2,843,555
Real estate, commercial \| Multi-family real estate
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	0
Allowance for credit loss, fee, and loan in process	619,489	537,015
Real estate, commercial \| Multi-family real estate \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	619,489	537,015
Real estate, commercial \| Multi-family real estate \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, commercial \| Multi-family real estate \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	0	0
Real estate, commercial \| Multi-family real estate \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	619,489	537,015
Real estate, mortgage \| Residential 1-4 family real estate
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	9,253	5,908
Allowance for credit loss, fee, and loan in process	1,728,367	1,736,453
Real estate, mortgage \| Residential 1-4 family real estate \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	1,712,092	1,720,305
Real estate, mortgage \| Residential 1-4 family real estate \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	5,733	6,685
Real estate, mortgage \| Residential 1-4 family real estate \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,289	3,555
Real estate, mortgage \| Residential 1-4 family real estate \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	1,728,367	1,736,453
Real estate, mortgage \| Home equity loans/lines of credit
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	3,024	2,407
Allowance for credit loss, fee, and loan in process	377,949	383,652
Real estate, mortgage \| Home equity loans/lines of credit \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	373,539	379,437
Real estate, mortgage \| Home equity loans/lines of credit \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	1,198	1,570
Real estate, mortgage \| Home equity loans/lines of credit \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	188	238
Real estate, mortgage \| Home equity loans/lines of credit \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	377,949	383,652
Consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	224	226
Allowance for credit loss, fee, and loan in process	68,692	67,458
Consumer loans \| Accruing Current
Financing Receivable, Past Due [Line Items]
Loans	68,114	66,692
Consumer loans \| Accruing 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	214	290
Consumer loans \| Accruing 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	140	250
Consumer loans \| Loans, Excluding Purchased Credit Impaired Loans
Financing Receivable, Past Due [Line Items]
Allowance for credit loss, fee, and loan in process	$ 68,692	$ 67,458

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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