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Debt Schedule of Debt Obligations (Details) € in Millions, $ in Millions, $ in Millions	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 18, 2018 USD ($)	Mar. 15, 2017 USD ($)	Mar. 15, 2017 EUR (€)	Jul. 07, 2016 CAD ($)	Jul. 07, 2016 USD ($)	Jul. 07, 2016 EUR (€)	Sep. 18, 2015 CAD ($)	May 03, 2012 USD ($)
Debt Instrument [Line Items]
Less: unamortized debt discounts and debt issuance costs	$ (56.7)	$ (64.8)
Total long-term debt (including current portion)	9,030.8	10,476.9
Less: current portion of long-term debt	921.3	1,583.1
Total long-term debt	8,109.5	8,893.8
Other short-term borrowings	6.9	11.4
Current portion of long-term debt and short-term borrowings	928.2	1,594.5
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount										$ 1,900.0
Senior Notes [Member] \| CAD 400 million 2.25% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount									$ 400
Debt instrument, interest rate percentage									2.25%
Senior Notes [Member] \| CAD 500 million 2.75% Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount									$ 500
Debt instrument, interest rate percentage									2.75%
Long-term debt, gross	384.9	366.6
Senior Notes [Member] \| CAD 500 million 2.84% notes due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 500
Debt instrument, interest rate percentage						2.84%	2.84%	2.84%
Long-term debt, gross	384.9	366.6
Senior Notes [Member] \| CAD 500 million 3.44% notes due 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 500	$ 500.0
Debt instrument, interest rate percentage						3.44%	3.44%	3.44%
Long-term debt, gross	384.9	366.6
Senior Notes [Member] \| $500 million 1.45% notes due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 500.0
Debt instrument, interest rate percentage						1.45%	1.45%	1.45%
Long-term debt, gross	0.0	500.0
Senior Notes [Member] \| $500 million 1.90% notes due 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate percentage				1.90%	1.90%
Long-term debt, gross	0.0	499.8
Senior Notes [Member] \| $500 million 2.25% notes due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 500.0	$ 500.0
Debt instrument, interest rate percentage				2.25%	2.25%
Long-term debt, gross	499.8	499.0
Senior Notes [Member] \| $1.0 billion 2.10% notes due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 1,000.0			$ 1,000.0
Debt instrument, interest rate percentage						2.10%	2.10%	2.10%
Long-term debt, gross	1,000.0	1,000.0
Senior Notes [Member] \| $500 million 3.5% notes due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount										$ 500.0
Debt instrument, interest rate percentage										3.50%
Long-term debt, gross	506.5	509.3
Senior Notes [Member] \| $2.0 billion 3.0% notes due 2026 [Member] [Domain]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 2,000.0
Debt instrument, interest rate percentage						3.00%	3.00%	3.00%
Long-term debt, gross	2,000.0	2,000.0
Senior Notes [Member] \| $1.1 billion 5.0% notes due 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount										$ 1,100.0
Debt instrument, interest rate percentage										5.00%
Long-term debt, gross	1,100.0	1,100.0
Senior Notes [Member] \| $1.8 billion 4.2% notes due 2046 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 1,800.0
Debt instrument, interest rate percentage						4.20%	4.20%	4.20%
Long-term debt, gross	1,800.0	1,800.0
Senior Notes [Member] \| Two Thousand Seventeen EUR Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €					€ 500.0
Long-term debt, gross	0.0	573.4
Senior Notes [Member] \| EUR 800 million 1.25% notes due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €								€ 800.0
Debt instrument, interest rate percentage						1.25%	1.25%	1.25%
Long-term debt, gross	897.0	917.4
Other Long-Term Debt [Member]
Debt Instrument [Line Items]
Long-term debt, gross	$ 129.5	$ 43.0