Total clinical trial costs incurred.

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- Definition

Contract

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- Definition

The percentage of the joint venture owned by others.

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- Definition

Research And Development Collaboration

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- Definition

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- Definition

Upfront License Payment

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- Definition

Revenue earned during the period arising from products sold or services provided under the terms of a contract, not elsewhere specified in the taxonomy. May include government contracts, construction contracts, and any other contract related to a particular project or product.

+ References

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 210.5-03.1)

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

The amount of receivables that are derived from government contracts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 912

-SubTopic 310

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6471842&loc=d3e55295-109406

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U.S. Government Agreement, Joint Venture and Collaborations (Details) (USD $)	3 Months Ended		12 Months Ended	72 Months Ended	1 Months Ended	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2012	Mar. 31, 2015	Oct. 31, 2014	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2011	Oct. 31, 2013
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Ownership percentage	20.00%			20.00%
Government contracts	$ 9,246,000us-gaap_ContractsRevenue	$ 5,472,000us-gaap_ContractsRevenue
Research and development collaborations	631,000	1,990,000
Trial costs incurred			2,900,000nvax_ClinicalTrialCostsIncurred
Cadila [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Joint Venture Percentage Owned By Others	80.00%			80.00%
HHS BARDA Contract [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Government contracts	3,100,000			87,000,000
Government Contract Receivable							97,000,000
HHS BARDA Option for Additional Period [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Government Contract Receivable							70,000,000
License Agreement with LG Life Sciences, Ltd. [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront license payment								2,500,000
PATH Vaccine Solutions [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and development collaborations	400,000			6,800,000
Research and development collaboration increase									400,000
Contract			$ 2,000,000		$ 1,000,000	$ 3,500,000