Debt (Summary of Long-Term Debt) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Current portion of long-term debt	$ 554.5	$ 655.2
Unamortized debt issuance expense	(63.8)	(73.7)
Long-term debt	12,460.5	13,161.2
Other Current Portion of Long-term Debt
Debt Instrument [Line Items]
Current portion of long-term debt	10.1	6.2
2016 Term Loans
Debt Instrument [Line Items]
Current portion of long-term debt	$ 0.0	100.0
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.705%
2019 Senior Notes (2.550% coupon)
Debt Instrument [Line Items]
Current portion of long-term debt	$ 0.0	549.9
2020 Floating Rate Euro Notes [Domain]
Debt Instrument [Line Items]
Current portion of long-term debt	544.9	0.0
Other
Debt Instrument [Line Items]
Long-term debt	$ 9.1	5.1
Senior Notes \| 2018 Senior Notes (2.600% coupon)
Debt Instrument [Line Items]
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.30%
Senior Notes \| 2018 Senior Notes (3.000% coupon)
Debt Instrument [Line Items]
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.30%
Senior Notes \| 2019 Senior Notes (2.500% coupon)
Debt Instrument [Line Items]
Stated percentage rate	2.50%
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.25%
Senior Notes \| 2019 Senior Notes (2.550% coupon)
Debt Instrument [Line Items]
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.20%
Senior Notes \| 2020 Floating Rate Euro Notes [Domain]
Debt Instrument [Line Items]
Long-term debt	$ 0.0	573.3
Basis spread on variable rate	0.50%
Senior Notes \| 2020 Euro Senior Notes
Debt Instrument [Line Items]
Stated percentage rate	1.25%
Long-term debt	$ 816.3	858.1
Senior Notes \| 2020 Senior Notes (3.750% coupon)
Debt Instrument [Line Items]
Stated percentage rate	3.75%
Long-term debt	$ 500.0	499.9
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.35%
Senior Notes \| 2021 Senior Notes (3.150% coupon)
Debt Instrument [Line Items]
Stated percentage rate	3.15%
Long-term debt	$ 2,249.1	2,248.7
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.30%
Senior Notes \| 2023 Senior Notes (3.125% coupon)
Debt Instrument [Line Items]
Stated percentage rate	3.125%
Long-term debt	$ 777.4	752.9
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.20%
Senior Notes \| 2023 Senior Notes (4.200% coupon)
Debt Instrument [Line Items]
Stated percentage rate	4.20%
Long-term debt	$ 499.1	498.9
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.25%
Senior Notes \| 2024 Euro Senior Notes
Debt Instrument [Line Items]
Stated percentage rate	2.25%
Long-term debt	$ 1,087.9	1,144.2
Senior Notes \| 2025 Euro Senior Notes [Member]
Debt Instrument [Line Items]
Stated percentage rate	2.125%
Long-term debt	$ 543.8	572.0
Senior Notes \| 2026 Senior Notes (3.950% coupon)
Debt Instrument [Line Items]
Stated percentage rate	3.95%
Long-term debt	$ 2,237.7	2,236.5
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.35%
Senior Notes \| 2028 Euro Senior Notes
Debt Instrument [Line Items]
Stated percentage rate	3.125%
Long-term debt	$ 810.8	852.5
Senior Notes \| SeniorNotesTwoThousandTwentyEight [Member]
Debt Instrument [Line Items]
Stated percentage rate	4.55%
Senior Notes \| 2028 Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 748.4	748.2
Senior Notes \| 2043 Senior Notes (5.400% coupon)
Debt Instrument [Line Items]
Stated percentage rate	5.40%
Long-term debt	$ 497.2	497.2
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.25%
Senior Notes \| 2046 Senior Notes (5.250% coupon)
Debt Instrument [Line Items]
Stated percentage rate	5.25%
Long-term debt	$ 999.8	999.8
Equivalent percentage of redeemed amount	100.00%
Basis spread on variable rate	0.40%
Senior Notes \| 2048 Senior Notes (5.200%)
Debt Instrument [Line Items]
Stated percentage rate	5.20%
Senior Notes \| 2048 Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 747.7	747.6
Current Portion of Long-Term Debt
Debt Instrument [Line Items]
Unamortized debt issuance expense	$ (0.5)	$ (0.9)

Percentage price equivalent at which long-term debt principal amount is redeemable prior to a specified date.

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

+ References

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

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- Definition

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.

+ References

No definition available.

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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