Credit Quality (Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment) (Parenthetical) (Detail) $ in Millions		12 Months Ended
		Dec. 31, 2016 USD ($) number		Dec. 31, 2015 USD ($) number		Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses		$ 1,253	[1]	$ 1,272	[1]	$ 1,322	$ 1,582
Portfolio loans and leases at fair value		143		167
Total loans and leases		$ 91,955	[2]	$ 92,415	[3]
Number of Contracts	[4],[5]	10,978		14,472		11,102
Recorded Investment		$ 1,901	[6]	$ 1,842	[7]
Variable Interest Entity, Primary Beneficiary
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses		26		28
Commercial | Variable Interest Entity, Primary Beneficiary
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses		$ 18		$ 15
Number of Contracts | number		5		5
Recorded Investment		$ 26		$ 27
Leveraged Leases
Financing Receivable, Allowance for Credit Losses
Allowance for loan and lease losses		2		5
Total loans and leases		701		801
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses
Portfolio loans and leases at fair value		$ 143		$ 167

[1] Includes $ 85 and $ 152 of cash and due from banks, $ 1,216 and $ 2,537 of portfolio loans and leases, $ (26) and $ (28) of ALLL, $ 9 and $ 14 of other assets, $ 3 and $ 3 of other liabilities and $ 1,094 and $ 2,487 of long-term debt from consolidated VIEs that are included in their respective captions above at December 31, 2016 and 2015 , respectively. For further information, refer to Note 11.

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

[3] Excludes $ 167 of residential mortgage loans measured at fair value at December 31, 2015 .

[4] Represents number of loans post-modification and excludes loans previously modified in a TDR .

[5] Excludes all loans and leases held for sale and loans acquired with deteriorated credit quality which were accounted for within a pool .

[6] Includes $ 322 , $ 635 and $ 323 , respectively, of commercial , residential mortgage and consumer portfolio TDRs on accrual status and $ 192 , $ 17 and $ 48 , respectively , of commercial, residential mortgage and consumer portfolio TDRs on nonaccrual status at December 31, 2016 .

[7] Includes $ 491 , $ 607 and $ 372 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on accrual status and $ 203 , $ 23 and $ 52 , respectively, of commercial, residential mortgage and consumer portfolio TDRs on nonaccrual status at December 31, 2015 .