Summary of Average Impaired Loans and Leases and Interest Income by Class (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended					12 Months Ended	3 Months Ended				9 Months Ended				3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	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, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Sep. 30, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Sep. 30, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary	Sep. 30, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary	Sep. 30, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary	Sep. 30, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 3,006	$ 2,963	$ 3,081		$ 2,829				$ 137	[1]	$ 145	[2]	$ 149	[1]	$ 140	[2]	$ 28	$ 29	$ 28	$ 30
Number of Contracts			6,916	[3],[4]	8,920	[3],[4]	5	5					25	[3],[4]	56	[3],[4],[5]

[1] Excludes five restructured loans 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 average recorded investment of $28 for the three and nine months ended September 30, 2014 and an immaterial amount of interest income recognized for the three and nine months ended September 30, 2014.

[2] Excludes five restructured loans 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 average recorded investment of $29 and $30 and an immaterial amount of interest income recognized for the three and nine months ended September 30, 2013.

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

[4] Represents number of loans post-modification.

[5] 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.