Summary of the Average Impaired Loans and Leases and Interest Income by Class (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 3,061		$ 2,942		$ 2,969
Number of Contracts	11,102	[1],[2]	11,291	[1],[2]	16,064	[1],[2]
Commercial Portfolio Segment | Commercial Mortgage Loans Owner Occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	149	[3]	146	[3]	156
Number of Contracts	32	[1],[2]	65	[1],[2],[4]	67	[1],[2]
Commercial Portfolio Segment | Commercial Mortgage Loans Owner Occupied [Member] | Variable Interest Entity, Primary Beneficiary
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 28		$ 28

[1] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality.

[2] Represents number of loans post-modification.

[3] Excludes five restructured nonaccrual loans at December 31, 2014 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 years ended December 31, 2014 and 2013 and an immaterial amount of interest income recognized for the years ended December 31, 2014 and 2013.

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