Consolidated Investment Entities (Debt of Consolidated Investment Entities) (Details 5) (Consolidated Investment Entities, USD $) In Millions, unless otherwise specified															6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Debt of Consolidated CDOs Maturing in 2016 to 2025 [Member]	Dec. 31, 2013 Debt of Consolidated CDOs Maturing in 2016 to 2025 [Member]	Jun. 30, 2014 Floating rate revolving credit borrowings due 2014	Dec. 31, 2013 Floating rate revolving credit borrowings due 2014	Jun. 30, 2014 Floating rate revolving credit borrowings due 2015	Dec. 31, 2013 Floating rate revolving credit borrowings due 2015	Jun. 30, 2014 Floating rate revolving credit borrowings due 2017	Dec. 31, 2013 Floating rate revolving credit borrowings due 2017	Jun. 30, 2014 Floating rate revolving credit borrowings due 2018	Dec. 31, 2013 Floating rate revolving credit borrowings due 2018	Jun. 30, 2014 Line of Credit Facility 2019 [Member]	Dec. 31, 2013 Line of Credit Facility 2019 [Member]	Jun. 30, 2014 Minimum	Jun. 30, 2014 Maximum
Debt and stated interest rates
Carrying value of debt	$ 6,672	$ 5,736	$ 5,511	$ 4,804	$ 347	$ 305	$ 105	$ 97	$ 123	$ 120	$ 428	$ 377	$ 158	$ 33
Weighted Average Interest Rate (as a percent)			1.20%	1.00%	2.30%	2.60%	2.40%	2.40%	4.60%	4.50%	2.70%	3.50%	3.30%	3.00%
Stated interest rate according to the terms of CDO structure (as a percent)															0.00%	9.20%
Fair value of floating rate debt of consolidated pooled investment vehicles managed by Threadneedle	1,200	932
Fair value of derivative instruments	$ 4	$ 5
Effective interest rate reflecting the impact of derivative contracts (as a percent)	3.30%	4.20%