Represent information pertaining to collaboration agreement upfront payment.

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- Definition

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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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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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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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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License agreements - Calithera (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			1 Months Ended		3 Months Ended				6 Months Ended		12 Months Ended
	Jan. 01, 2018	Jan. 30, 2017	Mar. 31, 2017	Jan. 31, 2017	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2018	Jan. 01, 2017
License agreements
Long term investment					$ 115,563				$ 115,563			$ 99,199
Research and development expense					289,363		$ 298,089		559,908	$ 601,192
Net income					105,318	$ 102,312	52,394	$ (41,140)	207,630	11,254
Unrealized gain (loss) on long term investments					(4,625)		(34,641)		16,364	(11,962)
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					5,400		3,200		10,000	5,800
Calithera \| Accrued and other liabilities
License agreements
Accrued and other liabilities					2,400				2,400
Calithera \| U.S.
License agreements
Percentage of profit (losses)				60.00%
Calithera
License agreements
Total consideration paid		$ 53,000		$ 53,000
Long term investment					$ 6,700				$ 6,700			6,900
Ownership percentage (as a percent)					4.00%				4.00%
Calithera \| Other Comprehensive Income
License agreements
Unrealized gain (loss) on long term investments					$ (4,900)		$ (2,200)		$ (200)	$ (5,800)
Calithera \| Calithera \| Accrued and other liabilities
License agreements
Accrued and other liabilities												$ 2,600
Calithera \| Stock purchase agreement
License agreements
Purchase of common stock under Stock Purchase Agreement (in shares )				1.7
Purchase price of common stock													$ 8,000
Per share price		$ 6.75											$ 4.65
Fair market value of our long term investments		$ 11,600
Stock purchase price				$ 8,000
Long term investment											$ 11,600
Research and development expense											$ 41,400
Calithera \| Collaboration and license agreement
License agreements
Upfront license fees				$ 45,000
Calithera \| ASU 2016-01
License agreements
Net income	$ 2,800