Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument
Unamortized issuing fees	$ (10.7)	$ (11.4)
Total debt	3,781.8	4,191.7
Less: current borrowings	80.7	67.4
Long-term debt	3,701.1	4,124.3
Line of Credit \| Revolving credit facility
Debt Instrument
Long-term debt, gross	0.0	0.0
Line of Credit \| Bilateral credit facilities
Debt Instrument
Long-term debt, gross	0.0	0.0
Commercial paper
Debt Instrument
Long-term debt, gross	1,431.2	1,916.1
Synthetic bonds due 2021
Debt Instrument
Long-term debt, gross	$ 493.8	$ 490.9
Senior Notes \| 3.45% Senior Notes due 2022
Debt Instrument
Interest rate, stated percentage	3.45%	3.45%
Long-term debt, gross	$ 500.0	$ 500.0
Private Placement Notes \| 5.00% 2010 Private placement notes due 2020
Debt Instrument
Interest rate, stated percentage	5.00%	5.00%
Long-term debt, gross	$ 227.4	$ 229.0
Private Placement Notes \| 3.40% 2012 Private placement notes due 2022
Debt Instrument
Interest rate, stated percentage	3.40%	3.40%
Long-term debt, gross	$ 170.6	$ 171.8
Private Placement Notes \| 3.15% 2013 Private placement notes due 2023
Debt Instrument
Interest rate, stated percentage	3.15%	3.15%
Long-term debt, gross	$ 147.8	$ 148.9
Private Placement Notes \| 3.15% 2013 Private placement notes due 2023
Debt Instrument
Interest rate, stated percentage	3.15%	3.15%
Long-term debt, gross	$ 142.2	$ 143.1
Private Placement Notes \| 4.00% 2012 Private placement notes due 2027
Debt Instrument
Interest rate, stated percentage	4.00%	4.00%
Long-term debt, gross	$ 85.3	$ 85.9
Private Placement Notes \| 4.00% 2012 Private placement notes due 2032
Debt Instrument
Interest rate, stated percentage	4.00%	4.00%
Long-term debt, gross	$ 113.7	$ 114.5
Private Placement Notes \| 3.75% 2013 Private placement notes due 2033
Debt Instrument
Interest rate, stated percentage	3.75%	3.75%
Long-term debt, gross	$ 113.7	$ 114.5
Bank borrowings
Debt Instrument
Long-term debt, gross	337.1	265.2
Other
Debt Instrument
Long-term debt, gross	$ 29.7	$ 23.2

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. 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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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