Additional Financial Information (Schedule Of Payables And Other Current Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Additional Information [Line Items]
Property and equipment, gross	$ 1,381.9	$ 1,318.9
Less: Accumulated depreciation	(1,052.8)	(951.1)
Property and equipment, net	329.1	367.8
Accounts payable	48.0	40.1
Accrued taxes	23.9	34.6
Accrued payroll-related expenses	140.6	156.4
Derivative Liabilities	29.7	21.4
Accrued expenses, other	69.0	84.5
Restructuring and exit costs	4.3	3.9
Deferred Revenue, Current	19.5	19.5
Accounts Payable and Accrued Liabilities, Current	335.0	360.4
Foreign currency translation adjustments	(38.2)	(1.1)	$ 35.1
Pension liability, net of tax benefit of $35.1 and $35.7	37.5	47.3	32.1
Unrealized gain (loss) on hedging activities, net of tax (expense) benefit of ($7.1) and $1.0	(26.1)	(18.3)	(22.5)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(101.8)	(66.7)	$ (19.5)
Land [Member]
Additional Information [Line Items]
Property and equipment, gross	6.9	6.9
Building [Member]
Additional Information [Line Items]
Property and equipment, gross	104.0	103.4
Leasehold Improvements [Member]
Additional Information [Line Items]
Property and equipment, gross	301.3	285.0
Equipment [Member]
Additional Information [Line Items]
Property and equipment, gross	578.6	555.8
Computer Software, Intangible Asset [Member]
Additional Information [Line Items]
Property and equipment, gross	356.0	339.2
Construction in Progress [Member]
Additional Information [Line Items]
Property and equipment, gross	$ 35.1	$ 28.6