Classifications of Consolidated VIE Assets, Liabilities and Noncontrolling Interest Included in the Bancorp's Consolidated Balance Sheets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2009
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks	$ 2,441	[1]	$ 2,663	[1]	$ 2,159	$ 2,318
Other short-term investments	2,421	[1]	1,781	[1]
Commercial mortgage loans	9,103	[1]	10,138	[1]
Home equity	10,018	[1]	10,719	[1]
Automobile loans	11,972	[1]	11,827	[1]
Allowance for loan and lease losses	(1,854)	[1]	(2,255)	[1]	(3,004)	(3,749)
Other assets	8,204	[1]	8,863	[1]
Total Assets	121,894		116,967		111,007
Other liabilities	2,639	[1]	3,270	[1]
Long-term debt	7,085	[1]	9,682	[1]
Total liabilities	108,130		103,716
Noncontrolling interests	48		50
Variable Interest Entity, Primary Beneficiary
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks			30
Other short-term investments			7
Commercial mortgage loans	50		50
Home equity			223
Automobile loans			259
Allowance for loan and lease losses	(5)		(10)
Other assets	3		4
Total Assets	48		563
Other liabilities			4
Long-term debt			191
Total liabilities			195
Noncontrolling interests	48		50
Variable Interest Entity, Primary Beneficiary | Home Equity
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks			5
Home equity			223
Allowance for loan and lease losses			(5)
Other assets			1
Total Assets			224
Long-term debt			22
Total liabilities			22
Variable Interest Entity, Primary Beneficiary | Automobile Loan
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks			25
Other short-term investments			7
Automobile loans			259
Allowance for loan and lease losses			(3)
Other assets			1
Total Assets			289
Other liabilities			4
Long-term debt			169
Total liabilities			173
Variable Interest Entity, Primary Beneficiary | Fifth Third Community Development Corporation Investments [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Commercial mortgage loans	50		50
Allowance for loan and lease losses	(5)		(2)
Other assets	3		2
Total Assets	48		50
Noncontrolling interests	$ 48		$ 50

[1] At December 31, 2012 and 2011, includes $0 and $30 of cash, $0 and $7 of other short-term investments, $50 and $50 of commercial mortgage loans, $0 and $223 of home equity loans, $0 and $259 of automobile loans, ($5) and ($10) of ALLL, $3 and $4 of other assets, $0 and $4 of other liabilities, $0 and $191 of long-term debt from consolidated VIEs that are included in their respective captions. See Note 10.