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Loans - Summary of loans (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Summary of Loans
Total loans	$ 47,667,911		$ 33,902,927
Less allowance for credit losses	(590,133)	$ (621,046)	(465,280)	$ (467,981)	$ (472,298)	$ (456,573)
Loans, net	47,077,778		33,437,647
Deferred costs	95,000		86,700
Unamortized Discounts	309,800		36,900
Accrued interest receivable (AIR)	$ 187,400		$ 133,000
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	$ 2,678,971		$ 2,184,327
Consumer owner-occupied
Summary of Loans
Total loans	8,441,314		7,144,885
Home equity loans
Summary of Loans
Total loans	1,760,712		1,570,084
Commercial and industrial
Summary of Loans
Total loans	8,644,636		6,222,876
Other income producing property
Summary of Loans
Total loans	1,267,183		607,750
Consumer
Summary of Loans
Total loans	987,085		1,062,599
Other loans
Summary of Loans
Total loans	22,913		10,298
Commercial loans
Summary of Loans
Total loans	36,137,245		23,705,601
Commercial loans \| Construction and land development
Summary of Loans
Total loans	2,328,743		1,798,096
Commercial loans \| Commercial non-owner-occupied
Summary of Loans
Total loans	16,336,022		9,383,732
Commercial loans \| Commercial non-owner occupied real estate
Summary of Loans
Total loans	7,529,075		5,716,376
Commercial loans \| Consumer owner-occupied
Summary of Loans
Total loans	124,457		66,910
Commercial loans \| Commercial and industrial
Summary of Loans
Total loans	8,644,636		6,222,876
Commercial loans \| Other income producing property
Summary of Loans
Total loans	1,151,399		507,313
Commercial loans \| Other loans
Summary of Loans
Total loans	22,913		10,298
Consumer loans
Summary of Loans
Total loans	11,530,666		10,197,326
Consumer loans \| Construction and land development
Summary of Loans
Total loans	350,228		386,231
Consumer loans \| Consumer owner-occupied
Summary of Loans
Total loans	8,316,857		7,077,975
Consumer loans \| Home equity loans
Summary of Loans
Total loans	1,760,712		1,570,084
Consumer loans \| Other income producing property
Summary of Loans
Total loans	115,784		100,437
Consumer loans \| Consumer
Summary of Loans
Total loans	$ 987,085		$ 1,062,599