Debt and Credit Facilities - Total Debt Outstanding (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Short-term borrowings	$ 84.0	$ 83.0
Current portion of long-term debt	2.0	297.0
Total current debt	86.0	380.0
Other	2.9	3.3
Total long-term debt, less current portion	3,219.4	3,762.6
Total debt	$ 3,305.4	$ 4,142.6
Short-term debt, weighted average interest rate	7.40%	4.80%
Long-term debt, weighted average interest rate	5.30%	4.70%
Unamortized discounts and issuance costs	$ 30.9	$ 36.3
Accounts Payable Under Financing Arrangements
Debt Instrument [Line Items]
Short-term borrowings	43.0
Line of Credit
Debt Instrument [Line Items]
Short-term borrowings	$ 41.0	83.0
6.50% Senior Notes due December 2020
Debt Instrument [Line Items]
Debt interest rate	6.50%
Senior notes	$ 423.4	423.1
4.875% Senior Notes due December 2022
Debt Instrument [Line Items]
Debt interest rate	4.875%
Senior notes	$ 420.2	419.6
5.25% Senior Notes due April 2023
Debt Instrument [Line Items]
Debt interest rate	5.25%
Senior notes	$ 420.2	419.7
4.50% Senior Notes due September 2023
Debt Instrument [Line Items]
Debt interest rate	4.50%
Senior notes	$ 467.9	416.7
5.125% Senior Notes due December 2024
Debt Instrument [Line Items]
Debt interest rate	5.125%
Senior notes	$ 420.6	420.2
5.50% Senior Notes due September 2025
Debt Instrument [Line Items]
Debt interest rate	5.50%
Senior notes	$ 396.6	396.4
6.875% Senior Notes due July 2033
Debt Instrument [Line Items]
Debt interest rate	6.875%
Senior notes	$ 445.4	445.3
Term Loan A due July 2019
Debt Instrument [Line Items]
Term loans	$ 222.2	$ 818.3

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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