Commitments, Contingent Liabilities and Guarantees - Additional Information (Detail) (USD $) Share data in Millions, unless otherwise specified	12 Months Ended																	3 Months Ended					3 Months Ended						12 Months Ended					12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2013 Residential Mortgage [Member]	Dec. 31, 2012 Residential Mortgage [Member]	Dec. 31, 2011 Residential Mortgage [Member]	Dec. 31, 2013 Standby Letters of Credit	Dec. 31, 2012 Standby Letters of Credit	Dec. 31, 2013 Standby Letters of Credit Secured Debt	Dec. 31, 2012 Standby Letters of Credit Secured Debt	Dec. 31, 2013 Variable Rate Demand Note [Member]	Dec. 31, 2012 Variable Rate Demand Note [Member]	Dec. 31, 2013 Other Liabilities	Dec. 31, 2012 Other Liabilities	Dec. 31, 2012 Private Mortgage Reinsurance	Jun. 30, 2011 Private Mortgage Reinsurance	Dec. 31, 2013 Private Mortgage Reinsurance	Dec. 31, 2013 Private Mortgage Reinsurance Minimum	Dec. 31, 2013 Private Mortgage Reinsurance Upper Limit	Sep. 30, 2012 Visa Litigation	Mar. 31, 2012 Visa Litigation	Dec. 31, 2011 Visa Litigation	Jun. 30, 2011 Visa Litigation	Dec. 31, 2010 Visa Litigation	Jun. 30, 2010 Visa Litigation	Dec. 31, 2009 Visa Litigation	Dec. 31, 2013 Visa Litigation	Dec. 31, 2012 Visa Litigation	Dec. 31, 2008 Visa Litigation	Dec. 31, 2007 Visa Litigation	Dec. 31, 2009 Visa	Dec. 31, 2008 Visa
Commitments and Contingencies Disclosure [Line Items]
Reserve for unfunded commitments										$ 2,000,000	$ 4,000,000					$ 162,000,000	$ 179,000,000
Percentage of the total standby letters of credit										97.00%	99.00%	48.00%	49.00%
Fifth Third Securities, Inc. (FTS) acted as the remarketing agent to issuers of VRDNs														1,800,000,000	2,500,000,000
Letters of credit	4,129,000,000		4,281,000,000											300,000,000	345,000,000
Total Variable Rate Demand Notes	2,100,000,000		2,800,000,000
Letters Credit Issued Related Variable Rate Demand Notes	1,500,000,000		2,000,000,000
Total outstanding reinsurance coverage																		58,000,000		37,000,000
Approximate reserve related to exposures within the reinsurance portfolio																10,000,000	18,000,000
Margin account balance held by the brokerage clearing agent	12,000,000		17,000,000
Fully and unconditionally guaranteed certain long-term borrowing obligations issued by wholly-owned issuing trust entities	50,000,000		800,000,000
Repurchase Claim Settlement	25,000,000
Reinsurance coverage ranges of the total PMI coverage																					5.00%	10.00%
Collateral Release Amount																			5,000,000
Increase (decrease) to the Bancorp's reserve liability																		(2,000,000)	(11,000,000)						54,000,000
Increase Decrease In Maximum Exposure To Loss																		(3,000,000)	(27,000,000)
Outstanding balances on residential mortgage loans sold with representation and warranty provisions							44,000,000	110,000,000	55,000,000
Outstanding balances on residential mortgage loans sold with credit recourse							579,000,000	662,000,000
Delinquency Rates							4.40%	5.90%
Credit loss reserve	1,582,000,000	[1]	1,854,000,000	[1]	2,255,000,000	3,004,000,000	16,000,000	20,000,000
Recognized liability equal to the fair value of the indemnification obligation																																	3,000,000
Recorded share of litigation formally settled by Visa and for probable future litigation settlements																													29,000,000	48,000,000	33,000,000	71,000,000	169,000,000
Visa IPO, shares of Visa's Class B common stock received																																			10.1
Received Class B common shares, carryover basis																																3,000,000,000			0
Sale of the Class B shares, recognition of the derivative liability and reversal of the net litigation reserve liability resulted in a pre-tax benefit																													288,000,000
Sale of the Class B shares, recognition of the derivative liability and reversal of the net litigation reserve liability resulted in an after-tax benefit																													187,000,000
Free-standing derivative liability initial fair value with reversal of net Visa litigation reserve																													55,000,000
Visa deposited into the litigation escrow account																							150,000,000		1,565,000,000	400,000,000	800,000,000	500,000,000	700,000,000
Reduction of liability in cash to the swap counterparty																							6,000,000	75,000,000		19,000,000	35,000,000	20,000,000
Cash Proceeds Sale Of Stock																																		300,000,000
Maximum Reasonably Possible Loss Related To Mortgage Representation And Warranty Provisions In Excess Of Reserve	$ 47,000,000

[1] At December 31, 2013 and 2012, includes $49 and $0 of cash and due from banks, $48 and $50 of commercial mortgage loans, $ 1,010 and $0 of automobile loans, $(15) and $(5) of ALLL, $13 and $3 of other assets, $1 and $0 of other liabilities, $ 1,048 and $0 of long-term debt from consolidated VIEs that are included in their respective captions. See Note 10.