Loans and Leases - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023		Mar. 31, 2022	Dec. 31, 2022		Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable
Unearned income	$ 262			$ 238
Net premium	51			146
Accrued interest receivable	548			518
Direct financing lease - interest income	6		$ 8
Sales type lease - interest income	15		11
Allowance for loan and lease losses	2,215	[1]	$ 1,908	2,194	[1]	$ 1,892
Commercial Leases
Accounts, Notes, Loans and Financing Receivable
Allowance for loan and lease losses	18			15
Federal Home Loan Bank Advances
Accounts, Notes, Loans and Financing Receivable
Loans pledged	15,800			15,900
FRB Loan
Accounts, Notes, Loans and Financing Receivable
Loans pledged	$ 56,100			$ 57,100

[1] Includes $5 and $17 of other short-term investments, $44 and $185 of portfolio loans and leases, $(1) and $(2) of ALLL, $0 and $2 of other assets, $9 and $9 of other liabilities, and $38 and $118 of long-term debt from consolidated VIEs that are included in their respective captions above at March 31, 2023 and December 31, 2022, respectively. For further information, refer to Note 12.