Non Purchased Loans - Summary of Non-Purchased Loans and Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Summary of loans
Gross loans	$ 11,110,164	$ 10,024,981
Unearned income	(5,160)	(4,067)
Loans, net of unearned income	11,105,004	10,020,914	$ 10,016,824
Commercial, financial, agricultural
Summary of loans
Gross loans	1,513,091	1,423,270
Loans, net of unearned income	1,513,091		1,436,019
Lease financing
Summary of loans
Gross loans	108,517	80,192
Loans, net of unearned income	103,357		79,215
Real estate – construction:
Summary of loans
Gross loans	1,215,056	1,104,896
Loans, net of unearned income	1,215,056		1,091,296
Real estate – construction: | Residential
Summary of loans
Gross loans	359,754	302,275
Real estate – construction: | Commercial
Summary of loans
Gross loans	855,302	802,621
Real estate – 1-4 family mortgage:
Summary of loans
Gross loans	3,127,889	2,724,246
Loans, net of unearned income	3,127,889		2,724,743
Real estate – 1-4 family mortgage: | Primary
Summary of loans
Gross loans	2,144,119	1,816,120
Real estate – 1-4 family mortgage: | Home equity
Summary of loans
Gross loans	499,626	474,604
Real estate – 1-4 family mortgage: | Rental/investment
Summary of loans
Gross loans	322,844	288,474
Real estate – 1-4 family mortgage: | Land development
Summary of loans
Gross loans	161,300	145,048
Real estate – commercial mortgage:
Summary of loans
Gross loans	5,016,665	4,549,037
Loans, net of unearned income	5,016,665		4,535,730
Real estate – commercial mortgage: | Land development
Summary of loans
Gross loans	133,597	128,739
Real estate – commercial mortgage: | Owner-occupied
Summary of loans
Gross loans	1,562,952	1,563,351
Real estate – commercial mortgage: | Non-owner occupied
Summary of loans
Gross loans	3,320,116	2,856,947
Installment loans to individuals
Summary of loans
Gross loans	128,946	143,340
Loans, net of unearned income	128,946		$ 149,821
Non purchased loans and leases
Summary of loans
Gross loans	10,265,000	9,015,078
Unearned income	(5,160)	(4,067)
Loans, net of unearned income	10,259,840	9,011,011
Non purchased loans and leases | Paycheck Protection Program
Summary of loans
Loans, net of unearned income	5,476	58,391
Non purchased loans and leases | Commercial, financial, agricultural
Summary of loans
Gross loans	1,435,275	1,332,962
Non purchased loans and leases | Lease financing
Summary of loans
Gross loans	108,517	80,192
Non purchased loans and leases | Real estate – construction:
Summary of loans
Gross loans	1,208,308	1,099,902
Non purchased loans and leases | Real estate – construction: | Residential
Summary of loans
Gross loans	359,367	300,988
Non purchased loans and leases | Real estate – construction: | Commercial
Summary of loans
Gross loans	848,941	798,914
Non purchased loans and leases | Real estate – 1-4 family mortgage:
Summary of loans
Gross loans	2,956,801	2,508,473
Non purchased loans and leases | Real estate – 1-4 family mortgage: | Primary
Summary of loans
Gross loans	2,041,885	1,682,050
Non purchased loans and leases | Real estate – 1-4 family mortgage: | Home equity
Summary of loans
Gross loans	456,765	423,108
Non purchased loans and leases | Real estate – 1-4 family mortgage: | Rental/investment
Summary of loans
Gross loans	306,165	268,245
Non purchased loans and leases | Real estate – 1-4 family mortgage: | Land development
Summary of loans
Gross loans	151,986	135,070
Non purchased loans and leases | Real estate – 1-4 family mortgage: | Land development
Summary of loans
Gross loans	151,986	135,070
Non purchased loans and leases | Real estate – commercial mortgage:
Summary of loans
Gross loans	4,451,853	3,885,984
Non purchased loans and leases | Real estate – commercial mortgage: | Owner-occupied
Summary of loans
Gross loans	1,368,196	1,329,219
Non purchased loans and leases | Real estate – commercial mortgage: | Non-owner occupied
Summary of loans
Gross loans	2,963,631	2,446,370
Non purchased loans and leases | Real estate – commercial mortgage: | Land development
Summary of loans
Gross loans	120,026	110,395
Non purchased loans and leases | Installment loans to individuals
Summary of loans
Gross loans	$ 104,246	$ 107,565