Licensing, Acquisitions, and Other Arrangements - Additional Information (Details) shares in Millions, $ in Millions	Jun. 01, 2016 USD ($) compound shares	Apr. 01, 2016 USD ($)
Stemcentrx
Business Acquisition [Line Items]
Number of early-stage clinical compounds in solid tumor indications acquired | compound	4
Shares issued as consideration (in shares) | shares	62.4
Additional payment	$ 4,000
Milestone payments	$ 620
Stemcentrx | IPR&D
Business Acquisition [Line Items]
Number of early-stage clinical compounds in solid tumor indications acquired | compound	4
BI
Business Acquisition [Line Items]
Initial upfront payment		$ 595
Additional payment		18
Milestone payments		606
Royalty payments		2,800
BI | Maximum
Business Acquisition [Line Items]
Additional payment		$ 1,600