Consolidated Investment Entities (Details 5) (Consolidated Investment Entities, USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Debt and stated interest rates
Carrying value of debt	$ 5,148	$ 4,981
Debt of consolidated CDOs due 2013-2025
Debt and stated interest rates
Carrying value of debt	4,595	4,450
Weighted Average Interest Rate (as a percent)	1.00%	0.90%
Floating rate revolving credit borrowings due 2014
Debt and stated interest rates
Carrying value of debt	288	309
Weighted Average Interest Rate (as a percent)	2.60%	2.60%
Floating rate revolving credit borrowings due 2015
Debt and stated interest rates
Carrying value of debt	97	104
Weighted Average Interest Rate (as a percent)	2.40%	2.40%
Floating rate revolving credit borrowings due 2017
Debt and stated interest rates
Carrying value of debt	111	118
Weighted Average Interest Rate (as a percent)	4.50%	4.50%
Floating rate revolving credit borrowings due 2018
Debt and stated interest rates
Carrying value of debt	$ 57
Weighted Average Interest Rate (as a percent)	3.70%