Credit Quality (Summary of the Credit Risk Profile of the Bancorp's Residential Mortgage and Consumer Portfolio Segments by Class) (Detail) - USD ($) $ in Millions		Sep. 30, 2018	Dec. 31, 2017
Total loans and leases		$ 93,271	$ 91,833
Residential Mortgage
Total loans and leases		15,413	15,454
Home Equity
Total loans and leases		6,485	7,014
Automobile Loans
Total loans and leases		9,002	9,112
Credit Card
Total loans and leases		2,325	2,299
Other consumer loans
Total loans and leases		2,131	1,559
Performing Financing Receivable
Total loans and leases		35,231	35,307
Performing Financing Receivable | Residential Mortgage | Residential Mortgage Loans
Total loans and leases	[1]	15,390	15,424
Performing Financing Receivable | Home Equity | Consumer Portfolio Segment
Total loans and leases		6,411	6,940
Performing Financing Receivable | Automobile Loans | Consumer Portfolio Segment
Total loans and leases		9,001	9,111
Performing Financing Receivable | Credit Card | Consumer Portfolio Segment
Total loans and leases		2,299	2,273
Performing Financing Receivable | Other consumer loans | Consumer Portfolio Segment
Total loans and leases		2,130	1,559
Nonperforming Financing Receivable
Total loans and leases		125	131
Nonperforming Financing Receivable | Residential Mortgage | Residential Mortgage Loans
Total loans and leases	[1]	23	30
Nonperforming Financing Receivable | Home Equity | Consumer Portfolio Segment
Total loans and leases		74	74
Nonperforming Financing Receivable | Automobile Loans | Consumer Portfolio Segment
Total loans and leases		1	1
Nonperforming Financing Receivable | Credit Card | Consumer Portfolio Segment
Total loans and leases		26	26
Nonperforming Financing Receivable | Other consumer loans | Consumer Portfolio Segment
Total loans and leases		$ 1	$ 0

[1] (a) Excludes $ 172 and $ 137 of residential mortgage loans measured at fair value at September 30, 2018 and December 31, 2017 , respectively.