Consolidated Statement of Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Interest income
Loans and leases, including fees	$ 8,021	$ 5,237	$ 3,749
Investment securities
Fully taxable	773	448	141
Exempt from federal taxes	66	51
Deposits at banks	1,360	509	48
Other	4	2	1
Total interest income	10,224	6,247	3,939
Interest expense
Savings and interest-checking deposits	1,746	271	33
Time deposits	671	24	19
Short-term borrowings	292	19
Long-term borrowings	400	111	62
Total interest expense	3,109	425	114
Net interest income	7,115	5,822	3,825
Provision for credit losses	645	517	(75)
Net interest income after provision for credit losses	6,470	5,305	3,900
Other income
Brokerage services income	102	88	63
Trading account and other non-hedging derivative gains	49	27	24
Gain (loss) on bank investment securities	4	(6)	(21)
Other revenues from operations	809	703	483
Total other income	2,528	2,357	2,167
Other expense
Salaries and employee benefits	2,997	2,787	2,046
Equipment and net occupancy	520	474	327
Outside data processing and software	437	376	292
Professional and other services	413	509	379
FDIC assessments	315	90	70
Advertising and marketing	108	90	64
Amortization of core deposit and other intangible assets	62	56	10
Other costs of operations	527	668	424
Total other expense	5,379	5,050	3,612
Income before taxes	3,619	2,612	2,455
Income taxes	878	620	596
Net income	2,741	1,992	1,859
Net income available to common shareholders
Basic	2,636	1,891	1,777
Diluted	$ 2,636	$ 1,891	$ 1,777
Net income per common share
Basic	$ 15.85	$ 11.59	$ 13.81
Diluted	$ 15.79	$ 11.53	$ 13.8
Mortgage Banking Revenues [Member]
Other income
Revenue from contract with customer	$ 409	$ 357	$ 571
Service Charges on Deposit Accounts [Member]
Other income
Revenue from contract with customer	475	447	402
Trust Income [Member]
Other income
Revenue from contract with customer	$ 680	$ 741	$ 645