Accumulated Other Comprehensive Loss (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Components of accumulated other comprehensive loss
Currency translation adjustments, net of tax benefit of (0.2) and $(0.2)	$ (17.1)	$ (17.1)
Funded status of pension liability, net of tax benefit of$(41.7) and $(24.8)	(70.7)	(42.1)
Unrealized loss on derivative financial instruments, net of tax benefit of $(34.9) and $(21.4)	(46.2)	(36.3)
Net amount recognized in other comprehensive income (loss)	$ (134.0)	$ (95.5)