Loans and Leases - Loans and Leases Classified by Primary Purpose (Details) - USD ($) $ in Millions		Mar. 31, 2025	Dec. 31, 2024
Loans and leases held for sale:
Loans held for sale		$ 473	$ 640
Portfolio loans and leases:
Total portfolio loans and leases	[1]	122,191	119,791
Commercial
Portfolio loans and leases:
Total portfolio loans and leases		75,137	73,293
Commercial | Commercial and industrial loans
Loans and leases held for sale:
Loans held for sale		28	15
Portfolio loans and leases:
Total portfolio loans and leases		53,700	52,271
Commercial | Commercial mortgage loans
Loans and leases held for sale:
Loans held for sale		0	22
Portfolio loans and leases:
Total portfolio loans and leases		12,357	12,246
Commercial | Commercial construction loans
Loans and leases held for sale:
Loans held for sale		0	29
Portfolio loans and leases:
Total portfolio loans and leases		5,952	5,588
Commercial | Commercial leases
Portfolio loans and leases:
Total portfolio loans and leases		3,128	3,188
Consumer
Portfolio loans and leases:
Total portfolio loans and leases		47,054	46,498
Consumer | Residential mortgage loans
Loans and leases held for sale:
Loans held for sale		445	574
Portfolio loans and leases:
Total portfolio loans and leases		17,581	17,543
Consumer | Home equity
Portfolio loans and leases:
Total portfolio loans and leases		4,265	4,188
Consumer | Indirect secured consumer loans
Portfolio loans and leases:
Total portfolio loans and leases		16,804	16,313
Consumer | Credit card
Portfolio loans and leases:
Total portfolio loans and leases		1,660	1,734
Consumer | Solar energy installation loans
Portfolio loans and leases:
Total portfolio loans and leases		4,262	4,202
Consumer | Other consumer loans
Portfolio loans and leases:
Total portfolio loans and leases		$ 2,482	$ 2,518

[1] Includes $47 and $51 of other short-term investments, $874 and $1,000 of portfolio loans and leases, $(16) and $(19) of ALLL, $6 and $5 of other assets, $12 and $12 of other liabilities and $774 and $889 of long-term debt from consolidated VIEs that are included in their respective captions above at March 31, 2025 and December 31, 2024, respectively. For further information, refer to Note 7.