Stock-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2010
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	23,215,000	[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	$ 69		$ 59	$ 64
Tax benefit for stock-based compensation expense	24		21	18
Weighted-average grant-date fair value per share	$ 4.23		$ 4.29	$ 5.10
Stock Appreciation Rights
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	four year period
Stock-based compensation expense	64
Weighted-average grant-date fair value per share	$ 14.36		$ 13.36	$ 14.74
Total grant-date fair value	22		20	25
Weighted-average period over which expense is expected to be recognized	2 years 9 months 18 days
Shares granted	12,179,000		8,633,000	5,310,000
Exercisable Weighted-Average Remaining Contractual Life	4 years 9 months 18 days
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
Stock-based compensation expense	57
Total grant-date fair value	32		37	30
Weighted-average period over which expense is expected to be recognized	2 years 8 months 12 days
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
Settled phantom stock units	199,813		521,091
Shares granted			132,649	488,703
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% 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	$ 14.36		$ 13.36	$ 13.76
Shares granted	344,741		328,061	61,320
Stock Options
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation	three or four year period
Intrinsic Value of Options Exercised	1
Cash received from options exercised	2		1
Aggregate intrinsic value of exercisable options	1
Employee Stock [Member]
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	8,720,000	[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	827,709		886,447	749,127

[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.