Acquisition of Isconova AB (Schedule of Purchase Price) (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended
Jul. 31, 2013
Acquisition Of Isconova AB [Abstract]
Value of shares of Novavax Common Stock issued	$ 41,942
Cash paid to Isconova warrant holders	22
Total purchase price	$ 41,964

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-Name Accounting Standards Codification

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Glossary Investing Activities

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