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Debt Schedule (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	May 03, 2012
Debt Instrument [Line Items]
Less: unamortized debt discounts	$ (54.6)	$ (56.7)
Total long-term debt (including current portion)	8,422.4	9,030.8
Current portion of long-term debt	(390.3)	(921.3)
Total long-term debt	8,032.1	8,109.5
Commercial Paper	25.5	0.0
Other short-term borrowings	29.2	6.9
Current portion of long-term debt and short-term borrowings	1,445.0	928.2
Finance leases and other [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	121.9	129.5
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 1,900.0
Senior Notes [Member] \| CAD 500 million 2.75% Notes Due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	355.6	384.9
Senior Notes [Member] \| CAD 500 million 2.84% notes due 2023 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	355.6	384.9
Senior Notes [Member] \| CAD 500 million 3.44% notes due 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	355.6	384.9
Senior Notes [Member] \| $500 million 2.25% notes due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	0.0	499.8
Senior Notes [Member] \| $1.0 billion 2.10% notes due 2021 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	1,000.0	1,000.0
Senior Notes [Member] \| $500 million 3.5% notes due 2022 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	505.8	506.5
Senior Notes [Member] \| $2.0 billion 3.0% notes due 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	2,000.0	2,000.0
Senior Notes [Member] \| $1.1 billion 5.0% notes due 2042 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	1,100.0	1,100.0
Senior Notes [Member] \| $1.8 billion 4.2% notes due 2046 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	1,800.0	1,800.0
Senior Notes [Member] \| EUR 800 million 1.25% notes due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	882.5	897.0
Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Short-term Debt	$ 1,000.0	$ 0.0