Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Interest income:
Loans, including fees	$ 1,189,377	$ 770,391	$ 674,611
Securities:
Taxable	406,289	249,797	89,550
Tax-exempt	240,131	237,626	226,683
Interest-bearing deposits	376,010	216,367	17,878
Federal funds sold	1,288	948	31
Resell agreements	4,621	592	16
Total interest income	2,217,716	1,475,721	1,008,769
Interest expense:
Deposits	508,255	140,476	14,520
Federal funds purchased	1,524	690	32
Repurchase agreements	135,969	34,443	2,209
Junior subordinated deferrable interest debentures	8,647	4,172	2,484
Subordinated notes	4,657	4,657	4,657
Total interest expense	659,052	184,438	23,902
Net interest income	1,558,664	1,291,283	984,867
Credit loss expense	46,171	3,000	63
Net interest income after credit loss expense	1,512,493	1,288,283	984,804
Non-interest income:
Trust and investment management fees	153,315	154,679	148,994
Service charges on deposit accounts	93,504	91,891	83,292
Insurance commissions and fees	58,271	53,210	51,548
Interchange and card transaction fees	19,419	18,231	17,461
Other charges, commissions and fees	49,026	41,590	36,836
Net gain (loss) on securities transactions	66	0	69
Other	54,941	45,217	48,528
Total non-interest income	428,542	404,818	386,728
Non-interest expense:
Salaries and wages	547,718	492,096	395,497
Employee benefits	115,306	88,608	82,029
Net occupancy	124,396	112,495	107,344
Technology, furniture and equipment	135,286	120,771	112,738
Deposit insurance	76,589	15,603	12,232
Other	229,367	194,701	172,154
Total non-interest expense	1,228,662	1,024,274	881,994
Income before income taxes	712,373	668,827	489,538
Income taxes	114,400	89,677	46,459
Net income	597,973	579,150	443,079
Preferred stock dividends	6,675	6,675	7,157
Net income available to common shareholders	$ 591,298	$ 572,475	$ 435,922
Earnings per common share:
Basic (in dollars per share)	$ 9.11	$ 8.84	$ 6.79
Diluted (in dollars per share)	$ 9.10	$ 8.81	$ 6.76