Condensed Financial Information (Parent Company Only) - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 682,122	$ 1,650,653
Loans	16,142,124	12,012,503
Other assets	622,520	325,793
Total assets	27,461,061	24,724,759
LIABILITIES
Long-term debt	390,285
Total liabilities	24,191,699	21,475,918
Stockholders’ equity:
Common stock	1,270	1,127
Surplus	2,530,066	2,164,989
Undivided profits	1,255,586	1,093,270
Total stockholders’ equity	3,269,362	3,248,841	$ 2,976,656	$ 2,988,924
Total liabilities and stockholders’ equity	27,461,061	24,724,759
Parent Company
ASSETS
Cash and cash equivalents	116,915	175,711
Investment securities	6,109	2,932
Investments in wholly-owned subsidiaries	3,453,961	3,444,624
Loans	1,412	2,610
Intangible assets, net	133	133
Premises and equipment	22,083	23,861
Other assets	80,513	53,877
Total assets	3,681,126	3,703,748
LIABILITIES
Long-term debt	386,798	406,552
Other liabilities	24,966	48,355
Total liabilities	411,764	454,907
Stockholders’ equity:
Preferred stock	0	0
Common stock	1,270	1,127
Surplus	2,530,066	2,164,989
Undivided profits	1,255,586	1,093,270
Unrealized depreciation on available-for-sale securities, net of income taxes of $(183,124) and $(3,731) at December 31, 2022 and 2021 respectively	(517,560)	(10,545)
Total stockholders’ equity	3,269,362	3,248,841
Total liabilities and stockholders’ equity	$ 3,681,126	$ 3,703,748