Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
INTEREST INCOME
Interest and fees on loans and leases		$ 2,113,615	$ 1,050,258	$ 890,515
Interest and dividends on investment securities:
Taxable		276,841	72,264	60,399
Exempt from federal income tax		24,109	5,351	5,947
Dividends		13,103	438	1,318
Interest on temporary investments and interest-bearing deposits		111,659	19,706	3,864
Total interest income		2,539,327	1,148,017	962,043
INTEREST EXPENSE
Interest on deposits		461,654	48,195	27,151
Interest on securities sold under agreement to repurchase and federal funds purchased		3,923	997	280
Interest on borrowings		242,914	8,920	2,838
Interest on junior and other subordinated debentures		37,665	19,889	12,127
Total interest expense		746,156	78,001	42,396
Interest Income (Expense), Net, Total		1,793,171	1,070,016	919,647
Provision (recapture) for credit losses		213,199	84,016	(42,651)
Net interest income after provision (recapture) for credit losses		1,579,972	986,000	962,298
NON-INTEREST INCOME
Revenue from Contract with Customer		134,259	85,825	83,312
Residential mortgage banking revenue (loss), net		16,789	106,859	186,811
Gain on sale of debt securities, net		13	2	8
Gain (loss) on equity securities, net		2,300	(7,099)	(1,511)
Gain on loan and lease sales, net		4,414	6,696	15,715
Bank owned life insurance income		15,624	8,253	8,302
Other income (loss)		30,528	(1,008)	63,681
Total non-interest income		203,927	199,528	356,318
NON-INTEREST EXPENSE
Salaries and employee benefits		616,103	441,226	480,820
Occupancy and equipment, net		183,480	138,451	137,546
Communications		16,252	10,429	11,564
Marketing		11,399	6,540	7,381
Services		57,641	51,323	48,800
FDIC assessments		71,402	13,964	9,238
Intangible amortization		111,296	4,095	4,520
Merger-related expenses		171,659	17,356	15,183
Other expenses		73,468	51,566	45,404
Total non-interest expense		1,312,700	734,950	760,456
Income before provision for income taxes		471,199	450,578	558,160
Income Tax Expense (Benefit)		122,484	113,826	137,860
Net Income (Loss) Attributable to Parent, Total		$ 348,715	$ 336,752	$ 420,300
Earnings Per Share [Abstract]
Basic earnings per common share (usd per share)	[1]	$ 1.79	$ 2.60	$ 3.22
Diluted earnings per common share (usd per share)	[1]	$ 1.78	$ 2.60	$ 3.21
Weighted average number of common shares outstanding:
Basic (in shares)	[1]	195,304	129,277	130,499
Diluted (in shares)	[1]	195,871	129,732	131,030
Service charges on deposits
NON-INTEREST INCOME
Revenue from Contract with Customer		$ 65,525	$ 48,365	$ 42,086
Card-based fees
NON-INTEREST INCOME
Revenue from Contract with Customer		55,263	37,370	36,114
Financial services and trust revenue
NON-INTEREST INCOME
Revenue from Contract with Customer		$ 13,471	$ 90	$ 5,112

[1] Periods prior to February 28, 2023 have been restated as a result of the adjustment to common shares outstanding based on the exchange ratio from the Merger of 0.5958.