Business Combinations (Details) (BioVex Group Inc [Member], USD $) In Millions, unless otherwise specified	Mar. 04, 2011
BioVex Group Inc [Member]
Aggregate acquisition date consideration to acquire an entity
Cash paid to former shareholders of acquired entity	$ 407
Fair value of contingent consideration obligations	190
Total consideration	$ 597

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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+ Details

- Definition

This element represents the acquisition-date fair value of the total consideration transferred which consists of the sum of the acquisition-date fair values of the assets transferred by the acquirer, the liabilities incurred by the acquirer to former owners of the acquiree, and the equity interests issued by the acquirer.

+ References+ Details