Gains and Losses (Realized and Unrealized) Included in Earnings for Level 3 Assets and Liabilities (Detail) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total gains (losses) included in earnings/OCI	$ (9)	$ (14)	$ (15)	$ (15)
Changes in unrealized gains (losses) relating to assets still held at reporting date	(5)	(4)	(7)	(1)
Other service fees
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total gains (losses) included in earnings/OCI	(10)	(9)	(16)	(10)
Changes in unrealized gains (losses) relating to assets still held at reporting date	(6)	(5)	(8)	(2)
Trading account profit
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total gains (losses) included in earnings/OCI	1	(5)	1	(5)
Changes in unrealized gains (losses) relating to assets still held at reporting date	$ 1	$ 1	$ 1	$ 1