Loans, Loan Composition (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Feb. 26, 2021
Loans and Leases Receivable [Line Items]
Loans	$ 29,216,218	$ 28,799,569	$ 0
Commercial and industrial
Loans and Leases Receivable [Line Items]
Loans	9,731,555	9,759,454
Commercial real estate - owner occupied
Loans and Leases Receivable [Line Items]
Loans	1,061,700	991,722
Commercial and business lending
Loans and Leases Receivable [Line Items]
Loans	10,793,255	10,751,176
Commercial real estate - investor
Loans and Leases Receivable [Line Items]
Loans	5,124,245	5,080,344
Real estate construction
Loans and Leases Receivable [Line Items]
Loans	2,271,398	2,155,222
Commercial real estate lending
Loans and Leases Receivable [Line Items]
Loans	7,395,644	7,235,565
Total commercial
Loans and Leases Receivable [Line Items]
Loans	18,188,898	17,986,742
Residential mortgage
Loans and Leases Receivable [Line Items]
Loans	7,864,891	8,511,550
Auto
Loans and Leases Receivable [Line Items]
Loans	2,256,162	1,382,073
Home equity
Loans and Leases Receivable [Line Items]
Loans	628,526	624,353
Other consumer
Loans and Leases Receivable [Line Items]
Loans	277,740	294,851
Total consumer
Loans and Leases Receivable [Line Items]
Loans	$ 11,027,319	$ 10,812,828