Fair Value Of Assets And Liabilities (Tri-Level Hierarchy, Carrying Value) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 257.7		$ 316.4
Seed Money	63.5	[1]	99.5	[2]
Investments related to deferred compensation plans	184.4	[1]	165.5	[2]
Corporate Stock	1.1		1.2	[2]
UITs	0.9		4.0	[2]
Municipal securities	1.1	[1]	9.9	[2]
Assets held for policyholders	1,243.5		1,295.4
Total current assets			1,891.9
CLOs			0.5	[2]
Total assets at fair value	1,752.2		1,892.4
Policyholder payables	(1,243.5)		(1,295.4)
Corporate equities	(1.0)		(0.7)
UIT-related derivative liabilities			(0.1)
Note payable	(16.8)		(18.9)
Total liabilities at fair value	(1,261.3)		(1,315.1)
Foreign time deposits	32.2		28.2
Other current investments	0.5		0.5
Equity method investments	193.1		156.9
Other non-current cost method investments	7.7		7.0
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	257.7		316.4
Seed Money	63.5	[1]	99.5	[2]
Investments related to deferred compensation plans	184.4	[1]	165.5	[2]
Corporate Stock	1.1		1.2	[2]
UITs	0.9		4.0	[2]
Municipal securities	0	[1]	0	[2]
Assets held for policyholders	1,243.5		1,295.4
Total current assets			1,882.0
CLOs			0	[2]
Total assets at fair value	1,751.1		1,882.0
Policyholder payables	(1,243.5)		(1,295.4)
Corporate equities	(1.0)		(0.7)
UIT-related derivative liabilities			(0.1)
Note payable	0		0
Total liabilities at fair value	(1,244.5)		(1,296.2)
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0		0
Seed Money	0	[1]	0	[2]
Investments related to deferred compensation plans	0	[1]	0	[2]
Corporate Stock	0		0	[2]
UITs	0		0	[2]
Municipal securities	1.1	[1]	9.9	[2]
Assets held for policyholders	0		0
Total current assets			9.9
CLOs			0	[2]
Total assets at fair value	1.1		9.9
Policyholder payables	0		0
Corporate equities	0		0
UIT-related derivative liabilities			0
Note payable	0		0
Total liabilities at fair value	0		0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0		0
Seed Money	0	[1]	0	[2]
Investments related to deferred compensation plans	0	[1]	0	[2]
Corporate Stock	0		0	[2]
UITs	0		0	[2]
Municipal securities	0	[1]	0	[2]
Assets held for policyholders	0		0
Total current assets			0
CLOs			0.5	[2]
Total assets at fair value	0		0.5
Policyholder payables	0		0
Corporate equities	0		0
UIT-related derivative liabilities			0
Note payable	(16.8)		(18.9)
Total liabilities at fair value	$ (16.8)		$ (18.9)

[1] Current foreign time deposits of $32.2 million and other current investments of $0.5 million are excluded from this table. Other non-current equity and cost method investments of $193.1 million and $7.7 million, respectively, are also excluded from this table. These investments are not measured at fair value, in accordance with applicable accounting standards.

[2] Current foreign time deposits of $28.2 million and other current investments of $0.5 million are excluded from this table. Other non-current equity and cost method investments of $156.9 million and $7.0 million, respectively, are also excluded from this table. These investments are not measured at fair value, in accordance with applicable accounting standards.