Commitments and Contingencies (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Commitments and Contingencies (Textual) [Abstract]
Deferred rent liability	$ 2.2		$ 2.2
Rent expense under operating leases	4.1	3.8	7.9	8.0
Outstanding letters of credit	12.7		12.7
Unfunded commitments in limited partnership interests	0.3		0.3
Liability related to various legal matters	43.6		43.6		3.0
Legal accruals and settlement charges	36.5	0.4	38.1	1.4
Maximum [Member] | Leaseholds and Leasehold Improvements [Member]
Loss Contingencies [Line Items]
Useful life			10 years
Commission Guarantees [Member]
Loss Contingencies [Line Items]
Maximum amount that could be paid under minimum commission guarantees	12.5		12.5
Liability for minimum commission guarantees	3.5		3.5
Weighted average remaining term			2 years 10 months 24 days
Payments of minimum commission guarantees			$ 0.5	$ 0.1
Percentage of estimated maximum annual payment			19.00%	21.00%