Classifications of Consolidated VIE Assets, Liabilities and Noncontrolling Interest Included in the Bancorp's Consolidated Balance Sheets (Detail) (USD $) In Millions	Sep. 30, 2011		Jun. 30, 2011	Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010	Dec. 31, 2009
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash and due from banks	$ 2,348	[1]		$ 2,159	[1]	$ 2,215	[1]		$ 2,318
Other short-term investments	2,028	[1]		1,515	[1]	3,271	[1]
Commercial mortgage loans	10,330	[1]		10,845	[1]	10,985	[1]
Home equity	10,920	[1]		11,513	[1]	11,774	[1]
Automobile loans	11,593	[1]		10,983	[1]	10,738	[1]
Allowance for loan and lease losses	(2,439)	[1]	(2,614)	(3,004)	[1]	(3,194)	[1]	(3,693)	(3,749)
Other assets	9,163	[1]		8,400	[1]	8,704	[1]
Total Assets	114,905			111,007		112,322
Other liabilities	3,372	[1]		2,979	[1]	3,082	[1]
Long-term debt	9,800	[1]		9,558	[1]	10,953	[1]
Total liabilities	101,847			96,927		98,409
Noncontrolling interest	29			29		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	35			52		56
Other short-term investments	7			7		7
Commercial mortgage loans	29			29		29
Home equity	228			241		248
Automobile loans	334			648		771
Allowance for loan and lease losses	(10)			(14)		(15)
Other assets	3			7		7
Total Assets	626			970		1,103
Other liabilities	5			12		17
Long-term debt	270			692		834
Total liabilities	275			704		851
Noncontrolling interest	29			29		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			7		5
Home equity	228			241		248
Allowance for loan and lease losses	(5)			(5)		(5)
Other assets	1			1		1
Total Assets	229			244		249
Long-term debt	26			133		147
Total liabilities	26			133		147
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	30			45		51
Other short-term investments	7			7		7
Automobile loans	334			648		771
Allowance for loan and lease losses	(4)			(8)		(9)
Other assets	1			5		5
Total Assets	368			697		825
Other liabilities	5			12		17
Long-term debt	244			559		687
Total liabilities	249			571		704
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	29			29		29
Allowance for loan and lease losses	(1)			(1)		(1)
Other assets	1			1		1
Total Assets	29			29		29
Noncontrolling interest	$ 29			$ 29		$ 29

[1] Includes $35, $52, and $56 of cash, $7, $7 and $7 of other short-term investments, $29, $29 and $29 of commercial mortgage loans, $228, $241 and $248 of home equity loans, $334, $648 and $771 of automobile loans, ($10), ($14) and ($15) of ALLL, $3, $7 and $7 of other assets, $5, $12 and $17 of other liabilities and $270, $692 and $834 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2011, December 31, 2010 and September 30, 2010, respectively. See Note 9.