Financial Instruments - Foreign Currency Derivatives (Details) (Foreign currency) In Millions, unless otherwise specified	Mar. 31, 2015 Chinese yuan Maturity June 2016 EUR (€)	Dec. 31, 2014 Chinese yuan Maturity June 2016 EUR (€)	Mar. 31, 2015 Chinese yuan Maturity December 2016 USD ($)	Dec. 31, 2014 Chinese yuan Maturity December 2016 USD ($)	Mar. 31, 2015 Euro Maturity December 2015 GBP (£)	Dec. 31, 2014 Euro Maturity December 2015 GBP (£)	Mar. 31, 2015 Euro Maturity February 2016 JPY (¥)	Dec. 31, 2014 Euro Maturity February 2016 JPY (¥)	Mar. 31, 2015 Euro Maturity April 2016 USD ($)	Dec. 31, 2014 Euro Maturity April 2016 USD ($)	Mar. 31, 2015 Japanese yen Maturity December 2015 USD ($)	Mar. 31, 2015 Japanese yen Maturity December 2015 CNY	Mar. 31, 2015 Japanese yen Maturity December 2015 KRW	Dec. 31, 2014 Japanese yen Maturity December 2015 USD ($)	Dec. 31, 2014 Japanese yen Maturity December 2015 CNY	Dec. 31, 2014 Japanese yen Maturity December 2015 KRW	Mar. 31, 2015 Korean won Maturity December 2015 USD ($)	Mar. 31, 2015 Korean won Maturity December 2015 EUR (€)	Mar. 31, 2015 Korean won Maturity December 2015 JPY (¥)	Dec. 31, 2014 Korean won Maturity December 2015 USD ($)	Dec. 31, 2014 Korean won Maturity December 2015 EUR (€)	Dec. 31, 2014 Korean won Maturity December 2015 JPY (¥)	Mar. 31, 2015 Mexican peso Maturity December 2015 USD ($)	Dec. 31, 2014 Mexican peso Maturity December 2015 USD ($)	Mar. 31, 2015 Swedish krona Maturity December 2015 EUR (€)	Dec. 31, 2014 Swedish krona Maturity December 2015 EUR (€)
Derivative [Line Items]
Notional amount of currency derivatives	€ 16.4	€ 0	$ 22.8	$ 24.9	£ 4.3	£ 5.7	¥ 3,751.7	¥ 4,371.8	$ 33.5	$ 23.5	$ 2.9	67.1	4,951.6	$ 3.8	88.6	6,712.5	$ 17.1	€ 7.6	¥ 590.1	$ 22.7	€ 2.5	¥ 72.0	$ 6.3	$ 22.6	€ 23.7	€ 31.4