Interim Financial Statements Schedule of Statements of Operations Data (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	$ 1,608,022	$ 1,470,116	$ 3,119,507	$ 2,789,107
Income from operations	622,188	550,312	1,189,419	980,854
Income before income taxes	656,074	525,850	1,241,472	958,139
Income tax expense	(104,662)	(138,106)	(212,080)	(321,464)
Net income	551,412	387,744	1,029,392	636,675
Balance Without Adoption of ASC 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	1,569,219		3,054,987
Income from operations	583,385		1,124,899
Income before income taxes	617,271		1,176,952
Income tax expense	(102,748)		(208,378)
Net income	514,523		968,574
Accounting Standards Update 2014-09 | Adjustments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	(38,803)		(64,520)
Income from operations	(38,803)		(64,520)
Income before income taxes	(38,803)		(64,520)
Income tax expense	1,914		3,702
Net income	(36,889)		(60,818)
Sanofi | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	237,753	222,128	427,243	432,495
Sanofi | Balance Without Adoption of ASC 606 | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	228,829		409,912
Sanofi | Accounting Standards Update 2014-09 | Adjustments | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	(8,924)		(17,331)
Other | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	111,024	$ 113,500	197,182	$ 169,940
Other | Balance Without Adoption of ASC 606 | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	81,145		149,993
Other | Accounting Standards Update 2014-09 | Adjustments | Product and service, other
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues	$ (29,879)		$ (47,189)