Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended						3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Pension Liability	Dec. 31, 2012 Pension Liability	Mar. 31, 2012 Pension Liability	Dec. 31, 2011 Pension Liability	Mar. 31, 2013 Net Unrealized Gains (Losses) From Marketable Securities	Mar. 31, 2012 Net Unrealized Gains (Losses) From Marketable Securities	Mar. 31, 2013 Net Unrealized Gains (Losses) From Hedges	Mar. 31, 2012 Net Unrealized Gains (Losses) From Hedges	Mar. 31, 2013 Foreign Currency Translation Adjustment	Mar. 31, 2012 Foreign Currency Translation Adjustment
Other Comprehensive Income (Loss)
Balance at the beginning of the period	$ (49.7)	$ (62.3)	$ (10.1)	$ (10.1)	$ (5.4)	$ (5.4)	$ 4.2	$ 1.8	$ (16.1)	$ 8.7	$ (27.7)	$ (67.4)
Other comprehensive income before reclassifications	67.1	57.3					(1.9)	2.5	74.9	23.3	(5.9)	31.5
Amounts reclassified from accumulated other comprehensive income	4.6	(16.8)					0.8	(0.4)	3.8	(16.4)
Net current-period other comprehensive income	71.7	40.5					(1.1)	2.1	78.7	6.9	(5.9)	31.5
Balance at the end of the period	$ 22.0	$ (21.8)	$ (10.1)	$ (10.1)	$ (5.4)	$ (5.4)	$ 3.1	$ 3.9	$ 62.6	$ 15.6	$ (33.6)	$ (35.9)