Debt and Credit Facilities - Total Debt Outstanding (Details) € in Millions	Mar. 31, 2018 EUR (€)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Short-term borrowings		$ 155,700,000	$ 25,300,000
Current portion of long-term debt		1,600,000	2,200,000
Total current debt		157,300,000	27,500,000
Other		6,300,000	6,300,000
Total long-term debt, less current portion		3,247,900,000	3,230,500,000
Total debt		$ 3,405,200,000	$ 3,258,000,000
Short-term debt, weighted average interest rate	1.80%	1.80%	5.40%
Long-term debt, weighted average interest rate	5.30%	5.30%	5.30%
Unamortized discounts and issuance costs		$ 28,100,000	$ 29,500,000
Line of Credit
Debt Instrument [Line Items]
Short-term borrowings		64,300,000	23,200,000
Accounts Payable Under Financing Arrangements
Debt Instrument [Line Items]
Short-term borrowings			2,100,000
European Accounts Receivable Securitization Program \| European Program
Debt Instrument [Line Items]
Amount of borrowing under securitization program	€ 74.4	$ 91,400,000	0
6.50% Senior Notes due December 2020
Debt Instrument [Line Items]
Debt interest rate	6.50%	6.50%
Senior notes		$ 423,700,000	423,600,000
4.875% Senior Notes due December 2022
Debt Instrument [Line Items]
Debt interest rate	4.875%	4.875%
Senior notes		$ 420,600,000	420,400,000
5.25% Senior Notes due April 2023
Debt Instrument [Line Items]
Debt interest rate	5.25%	5.25%
Senior notes		$ 420,600,000	420,400,000
4.50% Senior Notes due September 2023
Debt Instrument [Line Items]
Debt interest rate	4.50%	4.50%
Senior notes		$ 488,700,000	474,300,000
5.125% Senior Notes due December 2024
Debt Instrument [Line Items]
Debt interest rate	5.125%	5.125%
Senior notes		$ 420,900,000	420,700,000
5.50% Senior Notes due September 2025
Debt Instrument [Line Items]
Debt interest rate	5.50%	5.50%
Senior notes		$ 396,700,000	396,700,000
6.875% Senior Notes due July 2033
Debt Instrument [Line Items]
Debt interest rate	6.875%	6.875%
Senior notes		$ 445,400,000	445,400,000
Term Loan A due July 2019
Debt Instrument [Line Items]
Term loans		$ 225,000,000	$ 222,700,000

Amount of borrowing outstanding under accounts receivable securitization program.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Weighted average interest rate of long-term debt outstanding.

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding.

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