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, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Supplemental Cash Flow Information [Abstract]
Transfers from loans to other assets for other real estate owned (“OREO”)	$ 2	$ 1
Change in assets of consolidated VIEs	857	179
Change in liabilities of consolidated VIEs	1,049	27
Change in noncontrolling interests of consolidated VIEs	304	12
Securities not settled	1,177	1,167
Available-for-sale securities transferred to held-to-maturity	$ 11,602	$ 0