Consolidated Investment Products (Beginning And Ending Fair Value Measurements For Level 3 Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Beginning balance (Asset)	$ 0		$ 0
Transfers to Level 2	6.1
Ending balance (Asset)	13.2		13.2
Net unrealized gains/losses attributable to investments	6.0	42.6	8.0	39.5
Level 3 Assets [Member]
Beginning balance (Asset)	508.3	854.6	602.9	929.1
Purchases, Assets	8.3	6.2	21.6	6.7
Sales, Assets	(24.5)	(92.3)	(115.7)	(148.0)
Issuances, Assets	0	0	3.8	0
Settlements, Assets	0	0	0	0
Deconsolidation of CIP	0	0	(18.4)	0
Gain and losses included in the Condensed Consolidated Statement of Income, Level 3 Assets	14.7	23.3	19.2	14.5
Transfers to Level 2	0		(6.1)
Foreign exchange, Assets	0	4.8	(0.5)	(5.7)
Ending balance (Asset)	506.8	796.6	506.8	796.6
Level 3 Liabilities [Member]
Beginning balance (Liability)	(4,044.3)	(5,069.7)	(3,899.4)	(5,512.9)
Purchases, Liabilities	0	0	0	0
Sales, Liabilities	0	0	0	0
Issuances, Liabilities	(408.1)	(433.1)	(813.1)	(758.4)
Settlements, Liabilities	410.9	354.7	768.2	550.5
Deconsolidation of CIP	0	1,550.3	0	2,123.7
Gain and losses included in the Condensed Consolidated Statement of Income, Level 3 Liabilities	43.7	(121.2)	(54.8)	(279.9)
Transfers to Level 2	0		0
Foreign exchange, Liabilities	(5.3)	(136.0)	(4.0)	22.0
Ending balance (Liability)	$ (4,003.1)	$ (3,855.0)	$ (4,003.1)	$ (3,855.0)