Fair Value Measurements (Details 1) SFr in Millions, $ in Millions	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2006 CHF (SFr)
Debt Instrument [Line Items]
Notes payable, carrying value	$ 5,931.1	$ 5,938.2
Debt instruments, fair value	6,111.0	6,483.3
Notes Payable to Fumedica
Debt Instrument [Line Items]
Notes payable, fair value	0.0	3.2
Notes payable, carrying value	0.0	3.2	SFr 61.4
2.900% Senior Notes due 2020
Debt Instrument [Line Items]
Notes payable, fair value	1,491.6	1,517.7
Notes payable, carrying value	1,476.2	1,482.4
3.625% Senior Notes due 2022
Debt Instrument [Line Items]
Notes payable, fair value	1,001.7	1,032.9
Notes payable, carrying value	995.2	994.3
4.050% Senior Notes due 2025
Debt Instrument [Line Items]
Notes payable, fair value	1,756.6	1,851.9
Notes payable, carrying value	1,737.4	1,736.3
5.200% Senior Notes due 2045
Debt Instrument [Line Items]
Notes payable, fair value	1,861.1	2,077.6
Notes payable, carrying value	$ 1,722.3	$ 1,722.0

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Fair value portion of notes payable.

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