Segments (Results of Operations and Average Assets by Segment) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019		Mar. 31, 2019		Mar. 31, 2018		Mar. 31, 2018		Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information
Net interest income			$ 1,082				$ 996
Provision for (benefit from) credit losses			90				13
Net interest income after provision for credit losses			992				983
Noninterest Income
Service charges on deposits			131				137
Wealth and asset management revenue			112				113
Corporate banking revenue			112				88
Card and processing revenue			79				79
Mortgage banking net revenue			56				56
Other noninterest income			592	[1]			460	[2]
Securities gains (losses), net			16				(11)
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			3				(13)
Total noninterest income			1,101				909
Noninterest Expense
Salaries, wages and incentives			479				447
Employee benefits			131				110
Net occupancy expense			75				75
Technology and communications			83				68
Equipment expense			30				31
Card and processing expense			31				29
Other noninterest expense			268				250
Total noninterest expense			1,097				1,010
Income (Loss) Before Income Taxes			996				882
Applicable income tax expense			221				181
Net income (loss)	$ 775		775		$ 701		701
Goodwill	4,321		4,321		2,462		2,462		$ 2,478	$ 2,445
Total Assets	167,853		167,853		141,383		141,383		146,069
Intersegment Elimination
Segment Reporting Information
Net interest income			0				0
Provision for (benefit from) credit losses			0				0
Net interest income after provision for credit losses			0				0
Noninterest Income
Service charges on deposits			0				0
Wealth and asset management revenue			(33)				(34)
Corporate banking revenue			0				0
Card and processing revenue			0				0
Mortgage banking net revenue			0				0
Other noninterest income			0				0
Securities gains (losses), net			0				0
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			0				0
Total noninterest income			(33)				(34)
Noninterest Expense
Salaries, wages and incentives			0				0
Employee benefits			0				0
Net occupancy expense			0				0
Technology and communications			0				0
Equipment expense			0				0
Card and processing expense			0				0
Other noninterest expense			(33)				(34)
Total noninterest expense			(33)				(34)
Income (Loss) Before Income Taxes			0				0
Applicable income tax expense			0				0
Net income (loss)			0				0
Goodwill	0		0		0		0
Total Assets	0		0		0		0
Branch Banking
Segment Reporting Information
Net interest income			584				466
Provision for (benefit from) credit losses			52				44
Net interest income after provision for credit losses			532				422
Noninterest Income
Service charges on deposits			64				66
Wealth and asset management revenue			36				37
Corporate banking revenue			1				1
Card and processing revenue			63				64
Mortgage banking net revenue			1				1
Other noninterest income			18	[1]			15	[2]
Securities gains (losses), net			0				0
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			0				0
Total noninterest income			183				184
Noninterest Expense
Salaries, wages and incentives			114				110
Employee benefits			29				26
Net occupancy expense			43				43
Technology and communications			1				1
Equipment expense			12				13
Card and processing expense			29				29
Other noninterest expense			212				215
Total noninterest expense			440				437
Income (Loss) Before Income Taxes			275				169
Applicable income tax expense			58				35
Net income (loss)			217				134
Goodwill	1,655		1,655		1,655		1,655		1,655	1,655
Total Assets	69,599		69,599		60,197		60,197
Commercial Banking
Segment Reporting Information
Net interest income			509				419
Provision for (benefit from) credit losses			20				(20)
Net interest income after provision for credit losses			489				439
Noninterest Income
Service charges on deposits			66				71
Wealth and asset management revenue			1				1
Corporate banking revenue			112				86	[3]
Card and processing revenue			15				14
Mortgage banking net revenue			0				0
Other noninterest income			33	[1]			49	[2]
Securities gains (losses), net			0				(2)
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			0				0
Total noninterest income			227				219
Noninterest Expense
Salaries, wages and incentives			87				70
Employee benefits			22				18
Net occupancy expense			7				7
Technology and communications			2				2
Equipment expense			6				5
Card and processing expense			2				1
Other noninterest expense			230				235
Total noninterest expense			356				338
Income (Loss) Before Income Taxes			360				320
Applicable income tax expense			66				64
Net income (loss)			294				256
Goodwill	630		630		630		630		630	613
Total Assets	74,377		74,377		58,712		58,712
Consumer Lending
Segment Reporting Information
Net interest income			63				59
Provision for (benefit from) credit losses			13				12
Net interest income after provision for credit losses			50				47
Noninterest Income
Service charges on deposits			0				0
Wealth and asset management revenue			0				0
Corporate banking revenue			0				0
Card and processing revenue			0				0
Mortgage banking net revenue			55				55
Other noninterest income			3	[1]			4	[2]
Securities gains (losses), net			0				0
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			3				(13)
Total noninterest income			61				46
Noninterest Expense
Salaries, wages and incentives			35				39
Employee benefits			10				11
Net occupancy expense			2				3
Technology and communications			2				1
Equipment expense			0				0
Card and processing expense			0				0
Other noninterest expense			52				52
Total noninterest expense			101				106
Income (Loss) Before Income Taxes			10				(13)
Applicable income tax expense			2				(3)
Net income (loss)			8				(10)
Goodwill	0		0		0		0		0	0
Total Assets	24,662		24,662		22,384		22,384
Wealth and Asset Management
Segment Reporting Information
Net interest income			49				43
Provision for (benefit from) credit losses			0				16
Net interest income after provision for credit losses			49				27
Noninterest Income
Service charges on deposits			0				0
Wealth and asset management revenue			108				109
Corporate banking revenue			0				1
Card and processing revenue			1				1
Mortgage banking net revenue			0				0
Other noninterest income			5	[1]			5	[2]
Securities gains (losses), net			0				0
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			0				0
Total noninterest income			114				116
Noninterest Expense
Salaries, wages and incentives			45				44
Employee benefits			11				10
Net occupancy expense			3				3
Technology and communications			0				0
Equipment expense			0				0
Card and processing expense			0				0
Other noninterest expense			71				74
Total noninterest expense			130				131
Income (Loss) Before Income Taxes			33				12
Applicable income tax expense			7				3
Net income (loss)			26				9
Goodwill	193		193		177		177		193	177
Total Assets	9,916		9,916		10,611		10,611
General Corporate and Other
Segment Reporting Information
Net interest income			(123)				9
Provision for (benefit from) credit losses			5				(39)
Net interest income after provision for credit losses			(128)				48
Noninterest Income
Service charges on deposits			1				0
Wealth and asset management revenue			0				0
Corporate banking revenue			(1)				0
Card and processing revenue			0				0
Mortgage banking net revenue			0				0
Other noninterest income			533	[1]			387	[2]
Securities gains (losses), net			16				(9)
Securities gains (losses), net - non-qualifying hedges on mortgage servcing rights			0				0
Total noninterest income			549				378
Noninterest Expense
Salaries, wages and incentives			198				184
Employee benefits			59				45
Net occupancy expense			20				19
Technology and communications			78				64
Equipment expense			12				13
Card and processing expense			0				(1)
Other noninterest expense			(264)				(292)
Total noninterest expense			103				32
Income (Loss) Before Income Taxes			318				394
Applicable income tax expense			88				82
Net income (loss)			230				312
Goodwill	1,843	[4]	1,843	[4]	0		0		$ 0	$ 0
Total Assets	$ (10,701)	[5]	$ (10,701)	[5]	$ (10,521)	[6]	$ (10,521)	[6]

[1] Includes impairment charges of $ 20 for branches and land. For more information refer to Note 8 and Note 25 .

[2] Includes impairment charges of $ 8 for branches and land. For more information refer to Note 8 and Note 25 .

[3] Includes impairment charges of $ 2 for operating lease equipment. For more information refer to Note 9 .

[4] Due to the timing of the MB Financial, Inc. acquisition, the Bancorp is in the process of completing its analysis of the allocatio n of the goodwill across its four business segments, therefore goodwill is presented as part of General Corporate and Ot her as of March 31, 2019 .

[5] Includes bank premises and equipment of $ 78 classified as held for sale. For more information refer to Note 8 .

[6] Includes ba nk premises and equipment of $ 20 classified as held for sale. For more information refer to Not e 8 .