Goodwill and Intangible Assets-Intangible Assets by Business Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Intangible Assets [Roll Forward]
Beginning Balance	$ 4,809		$ 5,152
Amortization	(86)	(96)	(96)
Foreign exchange translation	(27)		16
Other			0	[1]
Ending Balance	4,696	4,809	5,072
Investment Management
Intangible Assets [Roll Forward]
Beginning Balance	2,228		2,382
Amortization	(39)		(48)
Foreign exchange translation	(24)		13
Other			0	[1]
Ending Balance	2,165		2,347
Investment Services
Intangible Assets [Roll Forward]
Beginning Balance	1,732		1,922
Amortization	(47)		(48)
Foreign exchange translation	(3)		3
Other			(2)	[1]
Ending Balance	1,682		1,875
Other
Intangible Assets [Roll Forward]
Beginning Balance	849		848
Amortization	0		0
Foreign exchange translation	0		0
Other			2	[1]
Ending Balance	$ 849		$ 850

[1] Other changes in intangible assets include purchase price adjustments and certain other reclassifications.