Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment (Parenthetical) (Detail) $ in Millions		12 Months Ended
		Dec. 31, 2015 USD ($) number		Dec. 31, 2014 USD ($) number		Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses		$ 1,272	[1]	$ 1,322	[1]	$ 1,582	$ 1,854
Portfolio loans and leases at fair value		167		108
Notes Receivable Net		$ 92,415	[2]	$ 89,976	[3]
Number of Contracts	[4],[5]	14,472		11,102		11,291
Recorded Investment		$ 1,842	[6]	$ 2,233	[7]
Consolidated Variable Interest Entity
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses		28		22
Commercial | Consolidated Variable Interest Entity
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses		$ 15		$ 10
Number of Contracts | number		5		5
Recorded Investment		$ 27		$ 28
Leveraged Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses		5		6
Notes Receivable Net		801		874
Residential Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Portfolio loans and leases at fair value		$ 167		$ 108

[1] Includes $152 and $179 of cash and due from banks, $2,537 and $3,378 of portfolio loans and leases, $(28) and $(22) of ALLL, $20 and $25 of other assets, $3 and $5 of other liabilities and $2,493 and $3,434 of long-term debt from consolidated VIEs that are included in their respective captions above at December 31, 2015 and 2014, respectively. For further information, refer to Note 11.

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

[3] Excludes $108 of residential mortgage loans measured at fair value at December 31, 2014.

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

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

[6] 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.

[7] Includes $869, $485 and $420, respectively, of commercial, residential mortgage and consumer portfolio TDRs on accrual status and $214, $33 and $63, respectively, of commercial, residential mortgage and consumer portfolio TDRs on nonaccrual status at December 31, 2014.