Credit Quality (Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment) (Detail) - USD ($) $ in Millions	Sep. 30, 2017		Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	$ 192	[1]			$ 230	[2]
Collectively evaluated for impairment	893	[1]			911	[2]
Unallocated	120	[1]			112	[2]
Total allowance for loan and lease losses	1,205	[1],[3]	$ 1,226	$ 1,226	1,253	[2],[3]	$ 1,272	$ 1,299	$ 1,299	$ 1,272
Individually evaluated for impairment	1,587	[4]			1,927	[5]
Collectively evaluated for impairment	90,154	[4]			90,025	[5]
Loans acquired with deteriorated credit quality	2	[4]			3	[5]
Total portfolio loans and leases	91,743	[4],[6]			91,955	[5],[7]
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	89	[1]			118	[2],[8]
Collectively evaluated for impairment	688	[1]			713	[2]
Unallocated	0	[1]			0	[2]
Total allowance for loan and lease losses	777	[1]	817	817	831	[2]	854	873	873	840
Individually evaluated for impairment	600	[4]			904	[5],[8]
Collectively evaluated for impairment	55,969	[4]			55,548	[5]
Loans acquired with deteriorated credit quality	0	[4]			0	[5]
Total portfolio loans and leases	56,569	[4]			56,452	[5]
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	64	[1]			68	[2]
Collectively evaluated for impairment	26	[1]			28	[2]
Unallocated	0	[1]			0	[2]
Total allowance for loan and lease losses	90	[1]	93	93	96	[2]	96	98		100
Individually evaluated for impairment	658	[4]			652	[5]
Collectively evaluated for impairment	14,788	[4]			14,253	[5]
Loans acquired with deteriorated credit quality	2	[4]			3	[5]
Total portfolio loans and leases	15,448	[4]			14,908	[5]
Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	39	[1]			44	[2]
Collectively evaluated for impairment	179	[1]			170	[2]
Unallocated	0	[1]			0	[2]
Total allowance for loan and lease losses	218	[1]	206	206	214	[2]	207	211	211	217
Individually evaluated for impairment	329	[4]			371	[5]
Collectively evaluated for impairment	19,397	[4]			20,224	[5]
Loans acquired with deteriorated credit quality	0	[4]			0	[5]
Total portfolio loans and leases	19,726	[4]			20,595	[5]
Unallocated
Financing Receivable, Allowance for Credit Losses
Individually evaluated for impairment	0	[1]			0	[2]
Collectively evaluated for impairment	0	[1]			0	[2]
Unallocated	120	[1]			112	[2]
Total allowance for loan and lease losses	120	[1]	$ 110	$ 110	112	[2]	$ 115	$ 117	$ 117	$ 115
Individually evaluated for impairment	0	[4]			0	[5]
Collectively evaluated for impairment	0	[4]			0	[5]
Loans acquired with deteriorated credit quality	0	[4]			0	[5]
Total portfolio loans and leases	$ 0	[4]			$ 0	[5]

[1] Includes $ 1 related to leveraged leases at September 30, 2017 .

[2] Includes $ 2 related to leveraged leases at December 31, 2016 .

[3] Includes $ 116 and $ 85 of cash and due from banks, $ 1,532 and $ 1,216 of portfolio loans and leases , $ (8) and $ (26) of ALLL, $ 9 and $ 9 of other assets, $ 3 and $ 3 of other liabilities , and $ 1,491 and $ 1,094 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2017 and December 31, 2016 , respectively. For further information refer to Note 11 .

[4] Excludes $ 140 of residential mortgage loans measured at fair value and includes $ 7 09 of leveraged leases, net of unearned income at September 30, 2017 .

[5] Excludes $ 143 of residential mortga ge loans measured at fair value and includes $ 701 of leveraged leases, net of unearned income at December 31, 2016 .

[6] Excludes $ 140 of residential mortgage loans measured at fair value at September 30, 2017 .

[7] Excludes $ 143 of residential mortgage loans measured at fair value at December 31, 2016 .

[8] Includes five restructured loans at December 31, 2016 associated with a consolidated VIE in which the Bancorp had no continuing credit risk due to the risk being assumed by a third party, with a recorded investment of $ 26 and an ALLL of $ 18 . Refer to Note 11 for further discussion on the deconsolidation of a VIE associated with these loans in the third quarter of 2017.