Other Arrangements (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Apr. 30, 2014	Dec. 31, 2008	Dec. 31, 2015
Sale of HIV Protease Inhibitor Royalty Stream
Gross proceeds from sale of royalty rights receivable from GlaxoSmithKline		$ 160.0
Royalty purchase agreement deferred revenue			$ 26.0
Other nonoperating Income	$ 36.7

The aggregate amount of other income amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration