Description of business and significant accounting policies.

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Provision for VAT assessments.

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No definition available.

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Value Added Tax Potential Payment

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(3))
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Amount of noncash expense for share-based payment arrangement.

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 28
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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities.

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Description of Business and Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands, € in Millions, shares in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) shares	Mar. 31, 2019 USD ($) shares	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 EUR (€)	Dec. 31, 2019 USD ($)
Description Of Business And Significant Accounting Policies [Line Items]
Accumulated deficit				$ 2,275,749		$ 2,263,563
Cash, cash equivalents, and short-term investments				81,100
VAT receivable \| €			€ 3.9		€ 3.9
Provision for value added tax assessments	$ 4,200
Potential payment to tax authority			€ 4.3	$ 4,800
Equity-based compensation	$ 1,167	$ 1,257
Anti-dilutive securities excluded from computation of earnings per share (in shares) \| shares	29.6	16.9
Aequus Biopharma, Inc \| Affiliated Entity
Description Of Business And Significant Accounting Policies [Line Items]
Interest in majority-owned subsidiary			60.00%	60.00%