Summary of Loans Modified in a TDR (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended					12 Months Ended	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014 Variable Interest Entity, Primary Beneficiary	Dec. 31, 2013 Variable Interest Entity, Primary Beneficiary	Sep. 30, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Sep. 30, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Sep. 30, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts	6,916	[1],[2]	8,920	[1],[2]	5	5	25	[1],[2]	56	[1],[2],[3]
Financing Receivable Modifications Post Modification Recorded Investment	$ 387	[1]	$ 575	[1]			$ 53	[1]	$ 16	[1],[3]	$ 29
Allowance for Loan and Lease Losses, Adjustments, Net	22	[1]	8	[1]			(1)	[1]	(1)	[1],[3]	7
Allowance for Loan and Lease Losses, Write-offs			$ 1	[1]							$ 2

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

[2] Represents number of loans post-modification.

[3] Excludes five loans modified in a TDR during the nine months ended September 30, 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. The TDR had a recorded investment of $29, ALLL increased $7 upon modification, and a charge-off of $2 was recognized upon modification.