Stockholders' Equity Stockholder's Equity (Reclassification out of Other Comprehensive Income) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification out of Accumulated Other Comprehensive Income
Selling, general and administrative expense		$ (144.3)	$ (170.8)	$ (482.6)	$ (542.0)
Research and development expense		(25.9)	(29.9)	(91.7)	(84.6)
Net interest expense		(8.1)	(8.0)	(24.4)	(24.5)
Income before income taxes		102.0	260.6	450.9	799.5
Income tax (expense) benefit		(19.5)	(90.1)	(112.3)	(264.8)
Net income		82.5	170.5	338.6	534.7
Reclassification out of Accumulated Other Comprehensive Income | Hedging | Foreign Exchange Contract
Reclassification out of Accumulated Other Comprehensive Income
Revenue		(29.9)	(12.2)	(91.6)	(27.0)
Cost of sales		17.8	9.1	36.8	29.4
Selling, general and administrative expense		(0.4)		(1.3)
Research and development expense		0.1
Net interest expense		(1.8)		0.1
Income before income taxes		(14.2)	(3.1)	(56.0)	2.4
Income tax (expense) benefit		2.7	1.1	11.4	2.5
Net income		(11.5)	(2.0)	(44.6)	4.9
Reclassification out of Accumulated Other Comprehensive Income | Defined Pension and Other Post-retirement Benefits
Reclassification out of Accumulated Other Comprehensive Income
Amortization of actuarial gain (loss)	[1]	(7.7)	(4.7)	(23.3)	(14.0)
Amortization of prior service credit (cost)	[1]		0.1	(0.1)	0.2
Settlement cost	[1]	(2.0)		(2.0)
Income before income taxes		(9.7)	(4.6)	(25.4)	(13.8)
Income tax (expense) benefit		3.2	1.5	8.2	4.8
Net income		$ (6.5)	$ (3.1)	$ (17.2)	$ (9.0)

[1] (a) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 11 for additional details).