Operating Segments - Schedule of Financial Data for Business Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Average interest earning assets (unaudited)	$ 56,500,528	$ 48,067,381	$ 38,227,815
Interest income	3,138,891	1,976,683	1,334,226
Interest expense	1,473,413	321,043	124,325
Net interest income	1,665,478	1,655,640	1,209,901
Provision for credit losses	50,184	56,817	32,633
Net interest income after provision for credit losses	1,615,294	1,598,823	1,177,268
Non-interest income	225,729	206,793	155,013
Non-interest expense	1,162,691	1,024,949	691,542
Internal transfer expense (income)	0	0	0
Income Before Income Taxes	$ 678,332	$ 780,667	$ 640,739
Return on average interest earning assets (pre-tax) (unaudited)	1.20%	1.62%	1.68%
Consumer Banking
Segment Reporting Information [Line Items]
Average interest earning assets (unaudited)	$ 8,892,563	$ 8,133,665	$ 7,262,808
Interest income	367,986	272,295	238,715
Interest expense	223,819	48,843	19,117
Net interest income	144,167	223,452	219,598
Provision for credit losses	6,162	20,880	(6,807)
Net interest income after provision for credit losses	138,005	202,572	226,405
Non-interest income	86,743	56,506	72,063
Non-interest expense	82,557	73,105	78,853
Internal transfer expense (income)	107,639	121,220	81,423
Income Before Income Taxes	$ 34,552	$ 64,753	$ 138,192
Return on average interest earning assets (pre-tax) (unaudited)	0.39%	0.80%	1.90%
Commercial Banking
Segment Reporting Information [Line Items]
Average interest earning assets (unaudited)	$ 40,459,298	$ 33,796,688	$ 25,554,177
Interest income	2,518,988	1,556,182	1,018,674
Interest expense	1,018,328	202,948	67,265
Net interest income	1,500,660	1,353,234	951,409
Provision for credit losses	39,463	35,456	39,703
Net interest income after provision for credit losses	1,461,197	1,317,778	911,706
Non-interest income	51,909	79,695	35,600
Non-interest expense	141,029	118,919	108,577
Internal transfer expense (income)	480,593	491,507	286,335
Income Before Income Taxes	$ 891,484	$ 787,047	$ 552,394
Return on average interest earning assets (pre-tax) (unaudited)	2.20%	2.33%	2.16%
Treasury and Corporate Other
Segment Reporting Information [Line Items]
Average interest earning assets (unaudited)	$ 7,148,667	$ 6,137,028	$ 5,410,830
Interest income	251,917	148,206	76,837
Interest expense	231,266	69,252	37,943
Net interest income	20,651	78,954	38,894
Provision for credit losses	4,559	481	(263)
Net interest income after provision for credit losses	16,092	78,473	39,157
Non-interest income	87,077	70,592	47,350
Non-interest expense	939,105	832,925	504,112
Internal transfer expense (income)	(588,232)	(612,727)	(367,758)
Income Before Income Taxes	$ (247,704)	$ (71,133)	$ (49,847)
Return on average interest earning assets (pre-tax) (unaudited)	(3.47%)	(1.16%)	(0.92%)