Notes Payable and Long-Term Debt (Details) € in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2017 EUR (€)	Jul. 26, 2017 USD ($)	Jun. 29, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jul. 20, 2016 USD ($)
Debt Instrument [Line Items]
Short-term Debt, Weighted Average Interest Rate, at Point in Time	3.10%	3.10%				2.30%
Debt, Weighted Average Interest Rate						3.80%
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 2,119,500,000					$ 2,063,000,000
Current portion of long-term debt	15,800,000					19,400,000
Long-term debt, net of current portion	2,103,700,000					2,043,600,000
Long-term Debt, by Maturity [Abstract]
2018	84,600,000
2019	138,700,000
2020	252,700,000
2021	2,700,000
2022	600,400,000
After 2022	1,121,000,000
Total payments	2,200,100,000
Less: unamortized discounts	11,800,000
Total	2,188,300,000
Multi-currency revolving credit agreement, maximum borrowing capacity	1,500,000,000				$ 1,250,000,000
Estimated fair value of senior unsecured notes	2,209,100,000					2,081,400,000
Fair value higher than carrying value for senior unsecured notes	116,100,000					62,000,000
Outstanding letters of credit	31,400,000					32,300,000
Short Term Borrowings [Member]
Short-term debt
Total short-term debt	68,800,000					156,500,000
Senior Notes Due November 2016
Long-term Debt, by Current and Noncurrent [Abstract]
Debt instrument par value	$ 150,000,000
Debt instrument stated interest rate	5.75%	5.75%
Debt instrument maturity period	Nov. 01, 2016
Senior Notes Due October 2019
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 137,400,000					139,100,000
Debt instrument par value	$ 134,000,000
Debt instrument stated interest rate	8.00%	8.00%
Debt instrument maturity period	Oct. 01, 2019
Senior Notes Due September 2020
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 251,400,000					251,900,000
Debt instrument par value	$ 250,000,000
Debt instrument stated interest rate	4.625%	4.625%
Debt instrument maturity period	Sep. 15, 2020
Senior Notes Due November 2022
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 595,700,000					520,700,000
Debt instrument par value | €		€ 500
Debt instrument stated interest rate	1.80%	1.80%
Debt instrument maturity period	Nov. 07, 2022
Senior Notes Due March 2025
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 496,100,000					495,600,000
Debt instrument par value	$ 500,000,000
Debt instrument stated interest rate	3.375%	3.375%
Debt instrument maturity period	Mar. 15, 2025
Senior Notes Due February 2029
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 118,900,000					118,800,000
Debt instrument par value	$ 121,000,000
Debt instrument stated interest rate	7.125%	7.125%
Debt instrument maturity period	Feb. 15, 2029
Senior Notes Due March 2045
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	$ 493,500,000					493,300,000
Debt instrument par value	$ 500,000,000
Debt instrument stated interest rate	4.375%	4.375%
Debt instrument maturity period	Mar. 15, 2045
Multi Currency Revolving Credit Facility [Member]
Long-term Debt, by Maturity [Abstract]
Multi-currency revolving credit agreement, maximum borrowing capacity				$ 1,000,000,000
Revolving Credit Facility [Member]
Long-term Debt, by Maturity [Abstract]
Multi-currency revolving credit agreement, current borrowing capacity	$ 1,200,000,000
Commercial Paper [Member]
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt						50,800,000
Long-term Debt, by Maturity [Abstract]
Multi-currency revolving credit agreement, current borrowing capacity	1,200,000,000.0		$ 1,000,000,000.0
Term Loan Facilities And Other [Member]
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	26,500,000					43,600,000
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount							$ 384,000,000
Interest Rate Swap [Member] | Senior Notes Four [Member]
Long-term Debt, by Maturity [Abstract]
Derivative liabilities						3,900,000
Interest Rate Swap [Member] | Senior Notes Three [Member]
Long-term Debt, by Maturity [Abstract]
Derivative liabilities						1,300,000
Unamortized portion of debt derivative [Member] | Senior Notes Four [Member]
Long-term Debt, by Maturity [Abstract]
Derivative assets	2,900,000
Unamortized portion of debt derivative [Member] | Senior Notes Three [Member]
Long-term Debt, by Current and Noncurrent [Abstract]
Total long-term debt	2,700,000					$ 4,100,000
Long-term Debt, by Maturity [Abstract]
Derivative assets	$ 800,000