Other Balance Sheet Information (Additional Detail Related To Certain Balance Sheet Captions) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Other Balance Sheet Information [Abstract]
Prepaid taxes	$ 13.3	$ 27.6
Prepaid expenses	49.5	44.6
Other	5.2	5.4
Total other current assets	68.0	77.6
Investments in joint ventures	39.8	37.2
Deposits for real-estate leases	11.9	12.2
Other	38.4	32.6
Total other assets	90.1	82.0
Salaries and benefits	80.0	73.8
Incentive compensation	29.6	114.1
Profit sharing contribution	1.0	7.1
Customer credits, advanced payments and advanced billings	22.6	17.6
Dividends	2.1	38.2
Professional service fees	50.8	50.5
Interest accrued on debt	3.7	15.1
Accounts payable	16.8	16.4
Income taxes	12.6	23.4
Restructuring	0.2	0.2
Deferred rent-current portion	1.3	1.7
Pension and other post retirement employee benefits	3.8	3.8
Interest accrued on UTPs		29.7
Other	78.3	60.7
Total accounts payable and accrued liabilities	302.8	452.3
Pension and other post retirement employee benefits	192.6	187.5
Deferred rent-non-current portion	110.2	108.8
Interest accrued on UTPs	7.0	11.8
Legacy and other tax matters	53.5	52.6
Other	42.5	44.1
Total other liabilities	$ 405.8	$ 404.8