Revenues (Revenues by Product and by Geographic Area) (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)
Revenue from External Customer [Line Items]
Number of operating segments \| segment	1
Total product sales	$ 5,343	$ 5,199
Other revenues	211	265
Total revenues	5,554	5,464
Hedging gains	34	57
US [Member]
Revenue from External Customer [Line Items]
Total product sales	4,147	4,095
ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	1,196	1,104
Neulasta® [Member]
Revenue from External Customer [Line Items]
Total product sales	1,155	1,210
Neulasta® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	1,009	1,048
Neulasta® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	146	162
Enbrel [Member]
Revenue from External Customer [Line Items]
Total product sales	1,105	1,181
Enbrel [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	1,050	1,118
Enbrel [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	55	63
Sensipar® / Mimpara® [Member]
Revenue from External Customer [Line Items]
Total product sales	497	421
Sensipar® / Mimpara® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	409	337
Sensipar® / Mimpara® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	88	84
Prolia® [Member]
Revenue from External Customer [Line Items]
Total product sales	494	425
Prolia® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	320	279
Prolia® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	174	146
Aranesp® [Member]
Revenue from External Customer [Line Items]
Total product sales	454	511
Aranesp® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	225	278
Aranesp® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	229	233
XGEVA® [Member]
Revenue from External Customer [Line Items]
Total product sales	445	402
XGEVA® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	332	298
XGEVA® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	113	104
EPOGEN® [Member]
Revenue from External Customer [Line Items]
Total product sales	244	270
EPOGEN® [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	244	270
EPOGEN® [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	0	0
Other products [Member]
Revenue from External Customer [Line Items]
Total product sales	949	779
Other products [Member] \| US [Member]
Revenue from External Customer [Line Items]
Total product sales	558	467
Other products [Member] \| ROW [Member]
Revenue from External Customer [Line Items]
Total product sales	$ 391	$ 312

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Section S99
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
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