Parent Company Financial Information - Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net income	$ 280,338	$ 336,372	$ 59,553
Adjustments to reconcile net income to cash used in operating activities:
Share-based compensation expense	18,925	13,264	10,859
Loss on debt extinguishment	0	180	0
Deferred income tax expense (benefit)	5,899	28,807	(42,622)
Change in accrued expenses and other liabilities, net	6,512	(29,038)	(9,455)
Change in accrued interest receivable and other assets, net	74,532	59,234	20,609
Net cash provided by operating activities	411,032	320,215	212,298
Cash flows from investing activities:
Net cash provided by investing activities	(160,093)	(2,007,697)	570,483
Cash flows from financing activities:
Net change in short-term borrowings	(358,000)	548,000	(691,000)
Redemption of subordinated debentures	0	(171,153)	0
Proceeds from issuance of subordinated debt, net	0	0	147,359
Repurchase and retirement of common stock	0	(18,067)	0
Proceeds from exercise of stock options	873	1,001	1,652
Net cash provided by (used in) financing activities	545,607	1,111,419	(228,865)
Net change in cash and cash equivalents	796,546	(576,063)	553,916
Cash and cash equivalents, beginning of year	304,703	880,766	326,850
Cash and cash equivalents, end of year	1,101,249	304,703	880,766
Corporation
Cash flows from operating activities:
Net income	283,743	339,889	60,351
Adjustments to reconcile net income to cash used in operating activities:
Share-based compensation expense	18,925	13,264	10,859
Equity in undistributed earnings of subsidiary	(172,104)	(238,992)	(48,451)
Loss on debt extinguishment	0	2,877	0
Deferred income tax expense (benefit)	230	(429)	188
Change in accrued expenses and other liabilities, net	2,985	377	1,149
Change in accrued interest receivable and other assets, net	(2,345)	(12,840)	(8,443)
Net cash provided by operating activities	131,434	104,146	15,653
Cash flows from investing activities:
Net cash provided by investing activities	0	0	0
Cash flows from financing activities:
Net change in short-term borrowings	(8,000)	8,000	0
Redemption of subordinated debentures	0	(36,153)	0
Proceeds from issuance of subordinated debt, net	0	0	147,359
Cash dividends paid	(125,160)	(121,887)	(79,901)
Repurchase and retirement of common stock	0	(18,067)	0
Proceeds from exercise of stock options	873	1,001	1,652
Restricted stock surrendered and canceled	(8,918)	(6,384)	(1,653)
Net cash provided by (used in) financing activities	(141,205)	(173,490)	67,457
Net change in cash and cash equivalents	(9,771)	(69,344)	83,110
Cash and cash equivalents, beginning of year	27,483	96,827	13,717
Cash and cash equivalents, end of year	$ 17,712	$ 27,483	$ 96,827