Condensed Financial Information (Parent Company Only) - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
OPERATING ACTIVITIES
Net income	$ 175,057	$ 256,412	$ 271,156
Items not requiring (providing) cash
Stock-based compensation expense	12,189	15,317	15,868
Deferred income taxes	(2,460)	14,933	10,937
Changes in:
Other assets	263,969	(7,214)	(33,495)
Net cash provided by operating activities	540,979	322,198	277,780
INVESTING ACTIVITIES
Net collections (originations) of loans			2,333,893
Net collections (originations) of loans	(786,775)	(1,900,325)
Net cash used in investing activities	(183,593)	(946,233)	(2,537,736)
FINANCING ACTIVITIES
Stock repurchases	(40,322)	(111,133)	(132,459)
Dividends paid on preferred stock	0	0	(47)
Dividends paid on common stock	(100,962)	(94,096)	(78,845)
Retirement of preferred stock	0	0	(767)
Net cash (used in) provided by financing activities	(425,416)	(344,496)	438,457
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(68,030)	(968,531)	(1,821,499)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	682,122	1,650,653	3,472,152
CASH AND CASH EQUIVALENTS, END OF YEAR	614,092	682,122	1,650,653
Parent Company
OPERATING ACTIVITIES
Net income	175,057	256,412	271,156
Items not requiring (providing) cash
Stock-based compensation expense	12,189	15,317	15,868
Depreciation and amortization	1,637	1,981	1,805
Deferred income taxes	(1,742)	(652)	3,347
Equity in undistributed net income (loss) of bank subsidiaries	(41,775)	(72,778)	(76,299)
Changes in:
Other assets	37,720	(26,775)	(2,099)
Other liabilities	2,293	(28,745)	11,109
Net cash provided by operating activities	185,379	144,760	224,887
INVESTING ACTIVITIES
Net collections (originations) of loans	1,310	1,198
Net collections (originations) of loans			(2,139)
Net purchases of premises and equipment	(52)	(21)	(83)
Cash acquired (paid) in business combinations	0	60,126	(6,818)
Other, net	5,856	1,688	2
Net cash used in investing activities	7,114	62,991	(9,038)
FINANCING ACTIVITIES
Repayment of long-term debt, net	(1,664)	(57,436)	(1,563)
Cancellation of common stock, net	(2,021)	(3,882)
Issuance of common stock, net			1,460
Stock repurchases	(40,322)	(111,133)	(132,459)
Dividends paid on preferred stock	0	0	(47)
Dividends paid on common stock	(100,962)	(94,096)	(78,845)
Retirement of preferred stock	0	0	(767)
Net cash (used in) provided by financing activities	(144,969)	(266,547)	(212,221)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	47,524	(58,796)	3,628
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	116,915	175,711	172,083
CASH AND CASH EQUIVALENTS, END OF YEAR	$ 164,439	$ 116,915	$ 175,711