Loans and Leases Classified by Primary Purpose (Detail) - USD ($) $ in Millions		Dec. 31, 2015	Dec. 31, 2014
Loans and leases held for sale:
Loans and leases held for sale	[1]	$ 903	$ 1,261
Portfolio loans and leases:
Commercial and industrial loans		42,131	40,765
Commercial mortgage loans		6,957	7,399
Commercial construction loans		3,214	2,069
Commercial leases		3,854	3,720
Total commercial loans and leases		56,156	53,953
Residential mortgage loans		13,716	12,389
Home equity		8,301	8,886
Automobile loans		11,493	12,037
Credit card		2,259	2,401
Other consumer loans and leases		657	418
Total consumer loans and leases		36,426	36,131
Portfolio loans and leases	[2],[3]	92,582	90,084
Commercial Portfolio Segment | Commercial and Industrial Loans
Loans and leases held for sale:
Loans and leases held for sale		20	36
Commercial Portfolio Segment | Commercial mortgage loans
Loans and leases held for sale:
Loans and leases held for sale		34	11
Commercial Portfolio Segment | Commercial construction loans
Loans and leases held for sale:
Loans and leases held for sale			2
Commercial Portfolio Segment | Commercial leases
Loans and leases held for sale:
Loans and leases held for sale			1
Residential Portfolio Segment | Residential mortgage loans
Loans and leases held for sale:
Loans and leases held for sale		708	1,193
Consumer Portfolio Segment | Home equity
Loans and leases held for sale:
Loans and leases held for sale		35
Consumer Portfolio Segment | Automobile Loans
Loans and leases held for sale:
Loans and leases held for sale		4
Consumer Portfolio Segment | Credit Card
Loans and leases held for sale:
Loans and leases held for sale		101
Consumer Portfolio Segment | Other consumer loans and leases
Loans and leases held for sale:
Loans and leases held for sale		$ 1	$ 18

[1] Includes $519 and $561 of residential mortgage loans held for sale measured at fair value at December 31, 2015 and 2014, respectively.

[2] Includes $152 and $179 of cash and due from banks, $2,537 and $3,378 of portfolio loans and leases, $(28) and $(22) of ALLL, $20 and $25 of other assets, $3 and $5 of other liabilities and $2,493 and $3,434 of long-term debt from consolidated VIEs that are included in their respective captions above at December 31, 2015 and 2014, respectively. For further information, refer to Note 11.

[3] Includes $167 and $108 of residential mortgage loans measured at fair value at December 31, 2015 and 2014, respectively.