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Loans - Summary of loans (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Summary of Loans
Total loans	$ 49,496,783	$ 48,598,527
Less allowance for credit losses	(585,882)	(585,197)	$ (623,690)	$ (465,280)
Loans, net	48,910,901	48,013,330
Deferred costs	97,400	97,000
Unamortized Discounts	219,000	259,500
Accrued interest receivable (AIR)	$ 189,200	$ 186,500
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets.	Other Assets.
Construction and land development
Summary of Loans
Total loans	$ 2,592,908	$ 2,548,360
Consumer owner-occupied
Summary of Loans
Total loans	8,717,832	8,618,434
Home equity loans
Summary of Loans
Total loans	1,856,065	1,831,789
Commercial and industrial
Summary of Loans
Total loans	9,385,926	9,181,408
Other income producing property
Summary of Loans
Total loans	1,201,200	1,232,153
Consumer
Summary of Loans
Total loans	923,413	955,266
Other loans
Summary of Loans
Total loans	50,166	2,366
Commercial loans
Summary of Loans
Total loans	37,649,135	36,858,811
Commercial loans \| Construction and land development
Summary of Loans
Total loans	2,232,480	2,205,518
Commercial loans \| Commercial non-owner-occupied
Summary of Loans
Total loans	17,097,738	16,651,760
Commercial loans \| Consumer owner-occupied
Summary of Loans
Total loans	117,442	121,394
Commercial loans \| Commercial and industrial
Summary of Loans
Total loans	9,385,926	9,181,408
Commercial loans \| Other income producing property
Summary of Loans
Total loans	1,093,848	1,119,374
Commercial loans \| Other loans
Summary of Loans
Total loans	50,166	2,366
Consumer loans
Summary of Loans
Total loans	11,847,648	11,739,716
Consumer loans \| Construction and land development
Summary of Loans
Total loans	360,428	342,842
Consumer loans \| Consumer owner-occupied
Summary of Loans
Total loans	8,600,390	8,497,040
Consumer loans \| Home equity loans
Summary of Loans
Total loans	1,856,065	1,831,789
Consumer loans \| Other income producing property
Summary of Loans
Total loans	107,352	112,779
Consumer loans \| Consumer
Summary of Loans
Total loans	$ 923,413	$ 955,266