Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010	Dec. 31, 2009
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	34,283,000	[1]
The Bancorp's total overhang (potential dilution from share-based compensation)	9.00%
Stock options, SARs, restricted stock and performance units outstanding as a percentage of issued shares	6.00%
Stock-based compensation expense	$ 59		$ 64	$ 51
Tax benefit for stock-based compensation expense	21		18
Weighted-average grant-date fair value per share	$ 4.29		$ 5.10	$ 2.41
Cash received from options exercised	1
Shares granted			488,703
Stock Appreciation Rights
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	four year period
Weighted-average grant-date fair value per share	$ 13.36		$ 14.74	$ 4.05
Total grant-date fair value	20		25	26
Weighted-average period over which expense is expected to be recognized (years)	2.7
Stock-based compensation expense not yet recognized	47
Shares granted	8,633,000		5,310,000	8,398,000
Shares settled	5.1
Contractual term of share based compensation award, maximum (in years)	10
Restricted Stock
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	vest after four years, or ratably over three or four years or ratably after three years of continued employment
Total grant-date fair value	37		30	36
Weighted-average period over which expense is expected to be recognized (years)	2.2
Stock-based compensation expense not yet recognized	40
Performance Incentive Plan 2008 [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	4,500,000
2011 Incentive Compensation Plan
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	39,000,000
Phantom Stock Units [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Weighted-average grant-date fair value per share	$ 14.40		$ 12.80
Shares granted	132,649
Shares settled	521,091.0
Settlement terms of phantom stock units	Phantom stock units issued on or before June 12, 2010 were settled in cash upon the earlier to occur of June 15, 2011 or the executive’s death. Units issued thereafter will be settled in cash with 50% to be settled on June 15, 2012 and 50% to be settled on June 15, 2013. The amount paid on settlement of the phantom stock units is equal to the total amount of phantom stock units settled at the reported closing price of the Bancorp’s common stock on the settlement date.
Performance Units [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	three-year cliff vesting terms
Weighted-average grant-date fair value per share	$ 13.36		$ 13.76	$ 3.96
Shares granted	328,061		61,320	1,118,958
Stock Options
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	three or four year period
Employee Stock [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	9,548,000	[2]
Stock-based compensation expense	$ 1		$ 1	$ 1
Match on qualifying employees purchase of shares of the Bancorp's common stock	15.00%
Stock purchased by plan participants	886,447		749,127	1,343,632

[1] Under the 2011 Incentive Compensation Plan, 39 million shares plus up to 4.5 million shares from the 2008 Incentive Compensation Plan (the Predecessor Plan) of stock were authorized for issuance as incentive and nonqualified stock options, SARs, restricted stock and restricted stock units, performance units and performance restricted stock awards.

[2] Represents remaining shares of Fifth Third common stock under the Bancorp’s 1993 Stock Purchase Plan, as amended and restated, including an additional 1.5 million shares approved by shareholders on March 28, 2007 and an additional 12 million shares approved by shareholders on April 21, 2009.