Debt - Summary (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Debt
Total	$ 2,060.7	$ 1,914.5
Less: unamortized discount and debt issuance costs	(12.4)	(13.1)
Less: amounts due within one year and short-term borrowings	(101.2)	(92.0)
Total long-term debt	1,947.1	1,809.4
Unsecured revolving credit facility due September 30, 2021
Debt
Total	690.0	538.0
Unsecured term loan due from June 29, 2018 to September 30, 2021
Debt
Total	555.0	562.5
Senior unsecured notes due April 15, 2023
Debt
Total	500.0	500.0
Senior unsecured notes due November 15, 2036
Debt
Total	250.0	250.0
Other notes and revolving credit facilities
Debt
Total	$ 65.7	$ 64.0

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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