Loans and Leases - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020		Dec. 31, 2019		Jan. 01, 2020	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable
Unearned income	$ 280		$ 354
Net premium	251		249
Accrued interest receivable	350
Loans pledged at the FHLB	15,500		16,700
Loans pledged at the FRB	37,800		47,300
Direct financing lease - interest income	64		88
Sales type lease - interest income	28		13
Allowance for loan and lease losses	2,453	[1]	1,202	[1]	$ 653	$ 1,103	$ 1,196
Commercial Leases
Accounts, Notes, Loans and Financing Receivable
Allowance for loan and lease losses	$ 29		$ 17

[1] Includes $55 and $74 of other short-term investments, $756 and $1,354 of portfolio loans and leases, $(7) and $(7) of ALLL, $5 and $8 of other assets, $2 and $2 of other liabilities and $656 and $1,253 of long-term debt from consolidated VIEs that are included in their respective captions above at December 31, 2020 and 2019, respectively. For further information, refer to Note 13.