Condensed Consolidated Statements Of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Operating revenues:
Investment management fees	$ 818.0	$ 779.5	$ 2,390.0	$ 2,390.9
Service and distribution fees	196.1	189.1	572.2	599.2
Performance fees	3.0	2.6	38.9	14.0
Other	24.3	26.6	83.0	91.0
Total operating revenues	1,041.4	997.8	3,084.1	3,095.1
Operating expenses:
Employee compensation	330.9	305.5	954.0	929.7
Third-party distribution, service and advisory	327.2	314.4	960.9	980.7
Marketing	26.4	13.1	79.7	64.9
Property, office and technology	69.1	62.7	204.4	188.6
General and administrative	68.8	69.6	230.8	220.8
Transaction and integration	3.0	4.7	5.6	23.9
Total operating expenses	825.4	770.0	2,435.4	2,408.6
Operating income	216.0	227.8	648.7	686.5
Other income/(expense):
Equity in earnings of unconsolidated affiliates	5.2	8.1	21.8	25.6
Interest and dividend income	2.5	3.8	7.1	8.3
Interest income of consolidated investment products	68.7	79.6	206.4	233.6
Other gains/(losses) of consolidated investment products, net	(25.2)	(93.1)	(69.9)	(243.3)
Interest expense	(12.6)	(15.3)	(39.6)	(47.5)
Interest expense of consolidated investment products	(41.9)	(48.7)	(134.4)	(135.2)
Other gains and losses, net	18.4	(19.7)	29.3	(5.8)
Income before income taxes	231.1	142.5	669.4	522.2
Income tax provision	(74.2)	(59.1)	(210.1)	(210.1)
Net income	156.9	83.4	459.3	312.1
Net (income)/loss attributable to noncontrolling interests in consolidated entities, net	13.7	83.5	59.1	215.3
Net income attributable to common shareholders	$ 170.6	$ 166.9	$ 518.4	$ 527.4
Earnings per share:
- basic	$ 0.38	$ 0.36	$ 1.14	$ 1.13
- diluted	$ 0.38	$ 0.36	$ 1.14	$ 1.13
Dividends declared per share	$ 0.1725	$ 0.1225	$ 0.4675	$ 0.3550