Furniture, Equipment and Leasehold Improvements, net (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Property, Plant and Equipment [Abstract]
Furniture and equipment	$ 881.5	$ 881.5
Leasehold improvements	593.0	605.4
Land and buildings	111.6	114.5
Furniture, equipment and leasehold improvements	1,586.1	1,601.4
Less: Accumulated depreciation	(1,126.3)	(1,147.1)
Total furniture, equipment and leasehold improvements, net	459.8	454.3
Depreciation and amortization expense	$ 130.7	$ 129.0	$ 150.6