Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance		31,480,000
The Bancorp's total overhang (potential dilution from share-based compensation)		10.00%
Stock options, SARs, restricted stock and performance units outstanding as a percentage of issued shares		7.00%
Stock-based compensation expense		$ 100	$ 83	$ 78
Tax benefit for stock-based compensation expense		$ 36	$ 30	$ 28
Incentive Compensation Plan 2014
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance		36,000,000
Full value awards
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance		16,000,000
Stock Appreciation Rights
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period of share based compensation		four year period
Stock-based compensation expense		$ 45
Weighted-average grant-date fair value per share		$ 18.99	$ 21.63	$ 16.16
Total grant-date fair value		$ 35	$ 34	$ 29
Weighted-average period over which expense is expected to be recognized		2 years 4 months 24 days
Shares granted		5,219,000	4,526,000	10,267,000
Exercisable Weighted-Average Remaining Contractual Life (in years)		4 years 2 months 12 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 of continued employment.
Stock-based compensation expense		$ 101
Weighted-average grant-date fair value per share		$ 19.11	$ 21.61	$ 16.21
Total grant-date fair value		$ 43	$ 32	$ 40
Weighted-average period over which expense is expected to be recognized		2 years 8 months 12 days
Shares granted		4,250,000	3,264,000	3,583,000
Phantom Stock Units
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Settled phantom stock units				200,130
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 were settled in cash with 50% settled on June 15, 2012 and 50% settled on June 15, 2013. The amount paid on settlement of the phantom stock units was 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.
Stock Option
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Intrinsic Value of Options Exercised		$ 1	$ 1	$ 1
Cash received from options exercised		2	1	2
Aggregate intrinsic value of exercisable options		$ 1
Employee stock purchase plan
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Shares available for future issuance	[1]	6,813,000
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		617,829	599,101	690,039
Restricted Stock Units
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 of continued employment.
Stock-based compensation expense		$ 4
Weighted-average grant-date fair value per share		$ 19.58
Total grant-date fair value		$ 2
Weighted-average period over which expense is expected to be recognized		2 years 10 months 24 days
Shares granted		377,000
Performance Units
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		$ 19.48	$ 15.61	$ 16.15
Shares granted		458,355	322,567	348,595
Stock Appreciation Rights
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Weighted-average grant-date fair value per share		$ 5.52	$ 6.53	$ 4.56

[1] 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.