Related parties (Details) - ArmaGen $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Related Party Transaction [Line Items]
Amount paid for an equity stake and the license to develop and commercialize AGT-182	$ 2.5
Share of R&D credit recorded within R&D expense	7.2
Related parties, acrrued liabilities	$ 0.7
Percentage of equity stake	21.00%

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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