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Represents the amount of the milestone payment made under the license agreement.

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- Definition

Represents the percentage of future global development costs funded under the license agreement.

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No definition available.

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Represents the potential milestone payments to be made under the license agreement with profit sharing in effect.

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Represents the potential milestone payments to be made under the license agreement if profit sharing is terminated.

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Represents the upfront payment under the license agreement.

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No definition available.

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Represents the percentage of profits (losses).

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Represents the purchase of common stock under Stock Purchase Agreement.

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No definition available.

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Represents the purchase price of common stock under Stock Purchase Agreement.

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Represents the amount of the total consideration paid under purchase agreement during the period.

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Amount of expenses incurred but not yet paid nor invoiced, and liabilities classified as other.

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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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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Price of a single share of a number of saleable stocks of a company.

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Fair value amount of financial instruments classified in shareholders' equity.

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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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License agreements - Calithera (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended		12 Months Ended
	Jan. 30, 2017	Jan. 01, 2017	Mar. 31, 2017	Jan. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
License agreements
Long term investment					$ 134,356	$ 31,987
Unrealized Gain (Loss) on Securities					(24,275)	(3,261)	$ (4,581)
Research and development expense					1,326,361	$ 581,861	$ 479,514
Calithera
License agreements
Funding of future development costs (as a percent)				70.00%
Upfront payment made under license agreement				$ 45,000
Potential milestone payments to be made with profit sharing in effect				430,000
Potential milestone payments to be made with profit sharing terminated				$ 750,000
Milestone payment made under license agreement			$ 12,000
Research and development expense					23,400
Calithera \| Accrued and other liabilities
License agreements
Accrued and other liabilities					900
Calithera \| U.S.
License agreements
Percentage of profit (losses)				60.00%
Calithera \| Stock purchase agreement
License agreements
Purchase of common stock under Stock Purchase Agreement (in shares )	1,700,000	1,720,430
Purchase price of common stock		$ 8,000
Per share price	$ 6.75	$ 4.65
Fair market value of our long term investments	$ 11,600
Fair value of shares on the issuance date					14,400
Total consideration paid	53,000
Upfront license fees	45,000
Stock purchase price	$ 8,000
Long term investment					$ 11,600
Ownership percentage (as a percent)					5.00%
Research and development expense					$ 41,400
Calithera \| Stock purchase agreement \| Other Comprehensive Income
License agreements
Unrealized Gain (Loss) on Securities					$ 2,800