Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended									9 Months Ended	12 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Jun. 30, 2014	Dec. 31, 2013		Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2014 Variable Interest Entity, Primary Beneficiary	Dec. 31, 2013 Variable Interest Entity, Primary Beneficiary	Sep. 30, 2014 Commercial Variable Interest Entity, Primary Beneficiary	Dec. 31, 2013 Commercial Variable Interest Entity, Primary Beneficiary	Sep. 30, 2014 Leveraged Leases	Dec. 31, 2013 Leveraged Leases	Sep. 30, 2014 Residential Mortgage Loans	Dec. 31, 2013 Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses	$ 1,414	[1]	$ 1,677		$ 1,458	$ 1,582	[1]	$ 1,735	$ 1,854	$ 19	$ 15	$ 10	$ 11	$ 7	$ 9
Portfolio loans and leases at fair value																109	92
Portfolio loans and leases	90,515	[2]				88,522	[3]							880	881
Number of Contracts	6,916	[4],[5]	8,920	[4],[5]						5	5
Recorded Investment	$ 3,039	[6]				$ 3,353	[7]					$ 28	$ 28

[1] Includes $150 and $49 of cash and due from banks, $48 and $48 of commercial mortgage loans, $2,785 and $1,010 of automobile loans, $(19) and $(15) of ALLL, $26 and $13 of other assets, $7 and $1 of other liabilities, and $2,882 and $1,048 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2014 and December 31, 2013, respectively. See Note 10.

[2] Excludes $109 of loans measured at fair value.

[3] Excludes $92 of loans measured at fair value.

[4] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality which were accounted for within a pool.

[5] Represents number of loans post-modification.

[6] Includes $885, $1,190 and $420, respectively, of commercial, residential mortgage and consumer TDRs on accrual status; $201, $60 and $54, respectively, of commercial, residential mortgage and consumer TDRs on nonaccrual status.

[7] Includes $869, $1,241 and $444, respectively, of commercial, residential mortgage and consumer TDRs on accrual status; $228, $84 and $52, respectively, of commercial, residential mortgage and consumer TDRs on nonaccrual status. Excludes five restructured loans at December 31, 2013 associated with a consolidated VIE in which the Bancorp has no continuing credit risk due to the risk being assumed by a third party, with an unpaid principal balance of $28, a recorded investment of $28, and an allowance of $11.