Other Noninterest Income and Other Noninterest Expense (Other Nonint Income and Expense) (Detail) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
		Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Other Noninterest Income
Gain related to Vantiv acquisition of Worldpay				$ 414		$ 0		$ 0
Gain on sale of Worldpay, Inc. shares		$ (205)	$ (414)	(205)		(1,037)		0
Operating lease income				84		96		102
Private equity investment income				63		36		11
BOLI income				56		52		53
Cardholder fees				56		54		46
Consumer loan and lease fees				23		23		23
Banking center income				21		20		20
Income from the tax receivable agreement associated with Worldpay, Inc.				20		44		313
Insurance income				20		8		11
Net gain (losses) on loan sales				2		(2)		10
Equity method income from interest in Worldpay Holding, LLC				1		47		66
Loss on swap associated with the sale of Visa, Inc. class B shares				(59)		(80)		(56)
Net losses on disposition and impairment of bank premises and equipment				(43)		0	[1]	(13)	[1]
Valuation adjustments on the warrant associated with Worldpay Holding, LLC				0		0		64
Gain on sale of certain retail branch operations				0		0		19
Gain on sale and exercise of the warrant associated with Worldpay Holding, LLC				0		0		9
Other, net				24		22		10
Total other noninterest income				887	[2]	1,357	[3]	688	[4]
Other Noninterest Expense
Marketing				147		114		104
FDIC insurance and other taxes				119		127		126
Loan and lease				112		102		110
Operating Lease				76		87		86
Professional services fees				67		83		61
Losses and adjustments				61		59		73
Data processing				57		58		51
Travel				52		46		45
Postal and courier				35		42		46
Recruitment and education				32		35		37
Donations				21		28		23
Supplies				13		14		14
Insurance				13		12		15
Gain / loss on partnership investments				(4)		14		25
Provision for (benefit from) for the reserve for unfunded commitments				(30)		0		23
Other, net				219		186		187
Total other noninterest expense	[1]			$ 990		$ 1,007		$ 1,026

[1] Effective in the fourth quarter of 2018, Fifth Third retrospectively applied a change in its accounting policy for investments in affordable housing projects that qualify for LIHTC in accordance with ASU 2014-01. Refer to Note 1 for additional information.

[2] Includes impairment charges of $ 45 for branches and land. For more information refer to Note 7 and Note 26 .

[3] Includes impairment charges of $ 7 for branches and land. For more information refer to Note 7 and Note 26 .

[4] Includes impairment charges of $ 32 for branches and land. For more information refer to Note 7 .