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Loans - Summary of loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Summary of Loans
Total loans	$ 50,846,872		$ 48,598,527
Less allowance for credit losses	(586,664)	$ (585,882)	(585,197)	$ (621,046)	$ (623,690)	$ (465,280)
Loans, net	50,260,208		48,013,330
Deferred costs	84,100		97,000
Unamortized Discounts	185,900		259,500
Accrued interest receivable (AIR)	$ 187,600		$ 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	$ 2,982,968		$ 2,548,360
Consumer owner-occupied
Summary of Loans
Total loans	9,125,082		8,618,434
Home equity loans
Summary of Loans
Total loans	1,909,020		1,831,789
Commercial and industrial
Summary of Loans
Total loans	9,378,444		9,181,408
Other income producing property
Summary of Loans
Total loans	1,175,338		1,232,153
Consumer
Summary of Loans
Total loans	934,035		955,266
Other loans
Summary of Loans
Total loans	8,477		2,366
Commercial loans
Summary of Loans
Total loans	38,548,985		36,858,811
Commercial loans \| Construction and land development
Summary of Loans
Total loans	2,624,560		2,205,518
Commercial loans \| Commercial non-owner-occupied
Summary of Loans
Total loans	17,481,117		16,651,760
Commercial loans \| Commercial non-owner occupied real estate
Summary of Loans
Total loans	7,852,391		7,576,991
Commercial loans \| Consumer owner-occupied
Summary of Loans
Total loans	129,490		121,394
Commercial loans \| Commercial and industrial
Summary of Loans
Total loans	9,378,444		9,181,408
Commercial loans \| Other income producing property
Summary of Loans
Total loans	1,074,506		1,119,374
Commercial loans \| Other loans
Summary of Loans
Total loans	8,477		2,366
Consumer loans
Summary of Loans
Total loans	12,297,887		11,739,716
Consumer loans \| Construction and land development
Summary of Loans
Total loans	358,408		342,842
Consumer loans \| Consumer owner-occupied
Summary of Loans
Total loans	8,995,592		8,497,040
Consumer loans \| Home equity loans
Summary of Loans
Total loans	1,909,020		1,831,789
Consumer loans \| Other income producing property
Summary of Loans
Total loans	100,832		112,779
Consumer loans \| Consumer
Summary of Loans
Total loans	$ 934,035		$ 955,266