Represent information pertaining to collaboration agreement upfront payment.

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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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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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- Definition

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

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

Represents the upfront payment under the license agreement.

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No definition available.

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- Definition

Represents the percentage of profits (losses).

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No definition available.

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- Definition

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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Fair value of the entity's equity.

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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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

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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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No definition available.

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License Agreements - Calithera (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			1 Months Ended		3 Months Ended								12 Months Ended
	Jan. 01, 2018	Jan. 30, 2017	Mar. 31, 2017	Jan. 31, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2017
License agreements
Long term investment					$ 99,199				$ 134,356				$ 99,199	$ 134,356
Research and development expense													1,197,957	1,326,134	$ 581,861
Net income					69,063	$ 29,176	$ 52,394	$ (41,140)	(149,629)	$ 36,054	$ (12,484)	$ (187,083)	109,493	(313,142)	104,222
Unrealized gain (loss) on long term investments													(44,093)	(24,275)	$ (3,261)
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													12,000	23,400
Calithera \| Accrued and other liabilities
License agreements
Accrued and other liabilities					2,600				900				2,600	900
Calithera \| U.S.
License agreements
Percentage of profit (losses)				60.00%
Calithera
License agreements
Total consideration paid		$ 53,000
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
Fair value of shares on the issuance date					$ 6,900				14,400				$ 6,900	14,400
Total consideration paid		53,000
Upfront license fees		45,000
Stock purchase price		$ 8,000
Long term investment									$ 11,600					11,600
Research and development expense														41,400
Ownership percentage (as a percent)					4.50%								4.50%
Unrealized gain (loss) on long term investments													$ (7,500)	$ 2,800
Calithera \| ASU 2016-01
License agreements
Net income	$ 2,800