Intangible Assets by Type (Detail) (USD $) In Millions, unless otherwise specified					3 Months Ended		3 Months Ended		3 Months Ended		3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010	Mar. 31, 2012 Finite-lived Intangible Assets Year	Dec. 31, 2011 Finite-lived Intangible Assets	Mar. 31, 2012 Finite-lived Intangible Assets Customer Relationships Year	Dec. 31, 2011 Finite-lived Intangible Assets Customer Relationships	Mar. 31, 2012 Finite-lived Intangible Assets Customer Contracts - Investment Services Year	Dec. 31, 2011 Finite-lived Intangible Assets Customer Contracts - Investment Services	Mar. 31, 2012 Finite-lived Intangible Assets Other Intangible Assets Year	Dec. 31, 2011 Finite-lived Intangible Assets Other Intangible Assets	Mar. 31, 2012 Indefinite-lived Intangible Assets		Dec. 31, 2011 Indefinite-lived Intangible Assets		Mar. 31, 2012 Indefinite-lived Intangible Assets Customer Relationships		Dec. 31, 2011 Indefinite-lived Intangible Assets Customer Relationships		Mar. 31, 2012 Indefinite-lived Intangible Assets Trade Name		Dec. 31, 2011 Indefinite-lived Intangible Assets Trade Name
Intangible Assets by Major Class [Line Items]
Gross carrying amount	$ 7,276				$ 4,590		$ 2,104		$ 2,354		$ 132		$ 2,686	[1]			$ 1,318	[1]			$ 1,368	[1]
Accumulated amortization	(2,204)				(2,204)		(1,225)		(880)		(99)
Net carrying amount	$ 5,072	$ 5,152	$ 5,617	$ 5,696	$ 2,386	$ 2,473	$ 879	$ 920	$ 1,474	$ 1,517	$ 33	$ 36	$ 2,686	[1]	$ 2,679	[1]	$ 1,318	[1]	$ 1,313	[1]	$ 1,368	[1]	$ 1,366	[1]
Remaining weighted- average amortization period					12		12		13		5

[1] Intangible assets not subject to amortization have an indefinite life.