Financing (Long-Term Indebtedness) (Table) (Details) € in Millions, SFr in Millions, $ in Millions, ¥ in Billions	Dec. 31, 2019 USD ($)	Nov. 07, 2019 USD ($)	Sep. 18, 2019 USD ($)	Sep. 18, 2019 EUR (€)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 EUR (€)	May 11, 2017 USD ($)	May 11, 2017 JPY (¥)	Feb. 28, 2016 USD ($)	Feb. 28, 2016 JPY (¥)	Dec. 08, 2015 USD ($)	Dec. 08, 2015 CHF (SFr)	Sep. 15, 2015 USD ($)	Jul. 08, 2015 USD ($)	Jul. 08, 2015 EUR (€)	Dec. 31, 2019 CHF (SFr)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 CHF (SFr)	Dec. 31, 2018 EUR (€)	Dec. 31, 2018 JPY (¥)	Dec. 31, 2001 USD ($)
Debt Instrument [Line Items]
Long-term debt	$ 21,729.1																		$ 9,740.3
Other
Debt Instrument [Line Items]
Long-term debt	76.3																		66.7
Convertible debt | Zero-coupon LYONS due 2021
Debt Instrument [Line Items]
Long-term debt	$ 33.6																		56.2
Interest rate of debt instrument	0.00%															0.00%	0.00%	0.00%					2.375%
Debt instrument, face amount																							$ 830.0
Senior notes | 0.352% senior unsecured notes due 2021
Debt Instrument [Line Items]
Long-term debt	$ 275.8																		273.2
Interest rate of debt instrument	0.352%															0.352%	0.352%	0.352%
Debt instrument, redemption price, percentage	100.00%
Net proceeds from debt									$ 262.0	¥ 29.9
Debt instrument, face amount | ¥																		¥ 30.0				¥ 30.0
Senior notes | 1.7% senior unsecured notes due 2022
Debt Instrument [Line Items]
Long-term debt	$ 894.8																		913.2
Interest rate of debt instrument	1.70%															1.70%	1.70%	1.70%
Debt instrument, redemption price, percentage	99.651%
Debt instrument, face amount | €																	€ 800.0				€ 800.0
Senior notes | Floating rate senior unsecured notes due 2022
Debt Instrument [Line Items]
Long-term debt	$ 279.8																		285.7
Debt instrument, redemption price, percentage	100.147%
Basis spread percentage to determine floating interest rate	0.30%
Debt instrument, face amount | €																	€ 250.0				250.0
Senior notes | 2.05% senior unsecured notes due 2022
Debt Instrument [Line Items]
Long-term debt	$ 696.9																		0.0
Interest rate of debt instrument	2.05%	2.05%														2.05%	2.05%	2.05%
Debt instrument, redemption price, percentage	99.994%	99.994%
Debt instrument, face amount		$ 700.0
Senior notes | 2.2% senior unsecured notes due 2024
Debt Instrument [Line Items]
Long-term debt	$ 696.2																		0.0
Interest rate of debt instrument	2.20%	2.20%														2.20%	2.20%	2.20%
Debt instrument, redemption price, percentage	99.952%	99.952%
Debt instrument, face amount		$ 700.0
Senior notes | 2.5% senior unsecured notes due 2025
Debt Instrument [Line Items]
Long-term debt	$ 893.7																		912.6
Interest rate of debt instrument	2.50%															2.50%	2.50%	2.50%
Debt instrument, redemption price, percentage	99.878%
Debt instrument, face amount | €																	€ 800.0				800.0
Senior notes | 3.35% senior unsecured notes due 2025
Debt Instrument [Line Items]
Long-term debt	$ 497.3																		496.8
Interest rate of debt instrument	3.35%															3.35%	3.35%	3.35%
Debt instrument, redemption price, percentage	99.857%
Senior notes | 0.2% senior unsecured notes due 2026
Debt Instrument [Line Items]
Long-term debt	$ 1,392.3																		0.0
Interest rate of debt instrument	0.20%															0.20%	0.20%	0.20%
Debt instrument, redemption price, percentage	99.833%
Debt instrument, face amount | €																	€ 1,300.0				0.0
Senior notes | 0.3% senior unsecured notes due 2027
Debt Instrument [Line Items]
Long-term debt	$ 282.5																		279.9
Interest rate of debt instrument	0.30%															0.30%	0.30%	0.30%
Debt instrument, redemption price, percentage	100.00%
Debt instrument, face amount | ¥																		¥ 30.8				30.8
Senior notes | 1.2% senior unsecured notes due 2027
Debt Instrument [Line Items]
Long-term debt	$ 668.0																		682.0
Interest rate of debt instrument	1.20%															1.20%	1.20%	1.20%
Debt instrument, redemption price, percentage	99.682%
Debt instrument, face amount | €																	€ 600.0				600.0
Senior notes | 0.45% senior unsecured notes due 2028
Debt Instrument [Line Items]
Long-term debt	$ 1,390.1																		0.0
Interest rate of debt instrument	0.45%															0.45%	0.45%	0.45%
Debt instrument, redemption price, percentage	99.751%
Debt instrument, face amount | €																	€ 1,300.0				0.0
Senior notes | 2.6% senior unsecured notes due 2029
Debt Instrument [Line Items]
Long-term debt	$ 794.8																		0.0
Interest rate of debt instrument	2.60%	2.60%														2.60%	2.60%	2.60%
Debt instrument, redemption price, percentage	99.903%	99.903%
Debt instrument, face amount		$ 800.0
Senior notes | 0.75% senior unsecured notes due 2031
Debt Instrument [Line Items]
Long-term debt	$ 1,948.7																		0.0
Interest rate of debt instrument	0.75%															0.75%	0.75%	0.75%
Debt instrument, redemption price, percentage	99.92%
Debt instrument, face amount | €																	€ 1,800.0				0.0
Senior notes | 0.65% senior unsecured notes due 2032
Debt Instrument [Line Items]
Long-term debt	$ 487.8																		483.4
Interest rate of debt instrument	0.65%															0.65%	0.65%	0.65%
Debt instrument, redemption price, percentage	100.00%
Debt instrument, face amount | ¥																		¥ 53.2				¥ 53.2
Senior notes | 1.35% senior unsecured notes due 2039
Debt Instrument [Line Items]
Long-term debt	$ 1,383.6																		0.0
Interest rate of debt instrument	1.35%															1.35%	1.35%	1.35%
Debt instrument, redemption price, percentage	99.461%
Debt instrument, face amount | €																	€ 1,300.0				0.0
Senior notes | 3.25% senior unsecured notes due 2039
Debt Instrument [Line Items]
Long-term debt	$ 890.3																		0.0
Interest rate of debt instrument	3.25%	3.25%														3.25%	3.25%	3.25%
Debt instrument, redemption price, percentage	99.809%	99.809%
Debt instrument, face amount		$ 900.0
Senior notes | 4.375% senior unsecured notes due 2045
Debt Instrument [Line Items]
Long-term debt	$ 499.4																		499.3
Interest rate of debt instrument	4.375%															4.375%	4.375%	4.375%
Debt instrument, redemption price, percentage	99.784%
Senior notes | 1.8% senior unsecured notes due 2049
Debt Instrument [Line Items]
Long-term debt	$ 830.9																		0.0
Interest rate of debt instrument	1.80%															1.80%	1.80%	1.80%
Debt instrument, redemption price, percentage	99.564%
Debt instrument, face amount | €																	€ 750.0				€ 0.0
Senior notes | 3.4% senior unsecured notes due 2049
Debt Instrument [Line Items]
Long-term debt	$ 890.2																		0.0
Interest rate of debt instrument	3.40%	3.40%														3.40%	3.40%	3.40%
Debt instrument, redemption price, percentage	99.756%	99.756%
Debt instrument, face amount		$ 900.0
Senior notes | Euro-denominated senior unsecured notes, tranches
Debt Instrument [Line Items]
Net proceeds from debt														$ 2,400.0	€ 2,200.0
Senior notes | U.S. dollar-denominated senior unsecured notes
Debt Instrument [Line Items]
Net proceeds from debt													$ 2,000.0
Senior notes | Euronotes
Debt Instrument [Line Items]
Net proceeds from debt					$ 940.0	€ 843.0
Senior notes | 2027 and 2032 Yen notes
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%
Net proceeds from debt							$ 744.0	¥ 83.6
Senior notes | Biopharma euronotes
Debt Instrument [Line Items]
Net proceeds from debt			$ 6,800.0	€ 6,200.0
Senior notes | Biopharma notes
Debt Instrument [Line Items]
Net proceeds from debt		$ 4,000.0
Bonds | 0.5% senior unsecured bonds due 2023
Debt Instrument [Line Items]
Long-term debt	$ 558.9																		550.7
Interest rate of debt instrument	0.50%															0.50%	0.50%	0.50%
Debt instrument, redemption price, percentage	100.924%
Debt instrument, face amount | SFr																SFr 540				SFr 540
Bonds | 1.125% senior unsecured bonds due 2028
Debt Instrument [Line Items]
Long-term debt	$ 221.0																		$ 218.1
Interest rate of debt instrument	1.125%															1.125%	1.125%	1.125%
Debt instrument, redemption price, percentage	102.87%
Debt instrument, face amount | SFr																SFr 210				SFr 210
Bonds | Swiss franc-denominated senior unsecured bonds
Debt Instrument [Line Items]
Net proceeds from debt											$ 739.0	SFr 758
Debt instrument, face amount | SFr												SFr 100
Bonds | 0.0% senior unsecured bonds due 2017
Debt Instrument [Line Items]
Interest rate of debt instrument												0.00%
Commercial paper | U.S. dollar denominated and euro-denominated commercial paper
Debt Instrument [Line Items]
Long-term debt	$ 5,146.2