Supplemental information to the Consolidated Statement of Cash Flows- Noncash Investing and Financing Transactions that are Not Reflected in Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Supplemental Cash Flow Information [Abstract]
Transfers from loans to other assets for other real estate owned (“OREO”)	$ 1	$ 2
Change in assets of consolidated VIEs	101	7,601
Change in liabilities of consolidated VIEs	8	7,300
Change in noncontrolling interests of consolidated VIEs	81	197
Securities purchased not settled	86	1,177
Securities sales not settled	356	0
Available-for-sale securities transferred to held-to-maturity	0	11,602
Premises and equipment/capitalized software funded by capital lease obligations	$ 2	$ 34