Summary of Average Impaired Loans and Leases and Interest Income by Class (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended							12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Mar. 31, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied		Mar. 31, 2014 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary	Dec. 31, 2013 Commercial Portfolio Segment Commercial Mortgage Loans, Owner Occupied Variable Interest Entity, Primary Beneficiary
Average Recorded Investment	$ 3,202	$ 2,793	$ 162	[1]	$ 140	[1]	$ 28	$ 30

[1] Excludes five restructured loans associated with a consolidated variable interest entity 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 and $30 at March 31, 2014 and 2013, respectively.