Classifications of Consolidated VIE Assets, Liabilities and Noncontrolling Interest Included in the Bancorp's Consolidated Balance Sheets (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Mar. 31, 2012	Dec. 31, 2011		Jun. 30, 2011		Mar. 31, 2011	Dec. 31, 2010
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks	$ 2,393	[1]		$ 2,663	[1]	$ 2,380	[1]		$ 2,159
Other short-term investments	1,964	[1]		1,781	[1]	1,370	[1]
Commercial mortgage loans	9,662	[1]		10,138	[1]	10,233	[1]
Home equity	10,377	[1]		10,719	[1]	11,048	[1]
Automobile loans	11,739	[1]		11,827	[1]	11,315	[1]
Allowance for loan and lease losses	(2,016)	[1]	(2,126)	(2,255)	[1]	(2,614)	[1]	(2,805)	(3,004)
Other assets	8,720	[1]		8,863	[1]	8,254	[1]
Total Assets	117,543			116,967		110,805
Other liabilities	3,016	[1]		3,270	[1]	3,282	[1]
Long-term debt	9,685	[1]		9,682	[1]	10,152	[1]
Total liabilities	103,719			103,716		98,204
Noncontrolling interest	51			50		29
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	9			30		42
Other short-term investments	4			7		7
Commercial mortgage loans	51			50		29
Home equity				223		231
Automobile loans	75			259		424
Allowance for loan and lease losses	(3)			(10)		(11)
Other assets	3			4		4
Total Assets	139			563		726
Other liabilities	2			4		8
Long-term debt	73			191		365
Total liabilities	75			195		373
Noncontrolling interest	51			50		29
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		6
Home equity				223		231
Allowance for loan and lease losses				(5)		(5)
Other assets				1		1
Total Assets				224		233
Long-term debt				22		35
Total liabilities				22		35
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	9			25		36
Other short-term investments	4			7		7
Automobile loans	75			259		424
Allowance for loan and lease losses	(1)			(3)		(5)
Other assets	1			1		2
Total Assets	88			289		464
Other liabilities	2			4		8
Long-term debt	73			169		330
Total liabilities	75			173		338
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	51			50		29
Allowance for loan and lease losses	(2)			(2)		(1)
Other assets	2			2		1
Total Assets	51			50		29
Noncontrolling interest	$ 51			$ 50		$ 29

[1] Includes $9, $30 and $42 of cash, $4, $7 and $7of other short-term investments, $51, $50 and $29 of commercial mortgage loans, $0, $223 and $231 of home equity loans, $75, $259 and $424 of automobile loans, ($3), ($10) and ($11) of ALLL, $3, $4 and $4 of other assets, $2, $4 and $8 of other liabilities, $73, $191and $365 of long-term debt from consolidated VIEs that are included in their respective captions above at June 30, 2012, December 31, 2011 and June 30, 2011, respectively. See Note 8.