Loans and Leases - Loans and Leases Classified by Primary Purpose (Details) - USD ($) $ in Millions		Jun. 30, 2021	Dec. 31, 2020
Loans and leases held for sale:
Loans and leases held for sale	[1]	$ 5,730	$ 4,741
Portfolio loans and leases:
Commercial and industrial loans		47,564	49,665
Commercial mortgage loans		10,347	10,602
Commercial construction loans		5,871	5,815
Commercial leases		3,238	2,915
Residential mortgage loans		16,131	15,928
Home equity		4,545	5,183
Indirect secured consumer loans		15,192	13,653
Credit card		1,793	2,007
Other consumer loans		3,052	3,014
Total portfolio loans and leases	[2],[3]	107,733	108,782
Residential mortgage loans
Loans and leases held for sale:
Loans and leases held for sale		5,684	4,465
Residential mortgage loans | GNMA loans
Portfolio loans and leases:
Total portfolio loans and leases			39
Commercial
Portfolio loans and leases:
Total portfolio loans and leases		67,020	68,997
Commercial | Commercial and industrial loans
Loans and leases held for sale:
Loans and leases held for sale		11	230
Portfolio loans and leases:
Total portfolio loans and leases		47,564	49,665
Loans and leases related to SBA Paycheck Protection Program of CARES Act		3,700	4,800
Commercial | Commercial mortgage loans
Loans and leases held for sale:
Loans and leases held for sale		33	7
Commercial | Commercial construction loans
Loans and leases held for sale:
Loans and leases held for sale		2	0
Portfolio loans and leases:
Total portfolio loans and leases		5,871	5,815
Commercial | Commercial leases
Loans and leases held for sale:
Loans and leases held for sale		0	39
Portfolio loans and leases:
Total portfolio loans and leases		3,238	2,915
Consumer
Portfolio loans and leases:
Total portfolio loans and leases		$ 40,713	39,785
Consumer | Residential mortgage loans | GNMA loans
Portfolio loans and leases:
Total portfolio loans and leases			$ 39

[1] Includes $1,633 and $1,481 of residential mortgage loans held for sale measured at fair value at June 30, 2021 and December 31, 2020, respectively.

[2] Includes $151 and $161 of residential mortgage loans measured at fair value at June 30, 2021 and December 31, 2020, respectively.

[3] Includes $33 and $55 of other short-term investments, $455 and $756 of portfolio loans and leases, $(3) and $(7) of ALLL, $3 and $5 of other assets, $1 and $2 of other liabilities, and $400 and $656 of long-term debt from consolidated VIEs that are included in their respective captions above at June 30, 2021 and December 31, 2020, respectively. For further information, refer to Note 11.