Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Collaboration and license revenue	$ 8,258	$ 2,359
Operating expenses:
Research and development	58,813	39,858
Selling, general and administrative	14,751	9,005
Total operating expenses	73,564	48,863
Loss from operations	(65,306)	(46,504)
Interest and other income (expense), net	332	(409)
Net loss	(64,974)	(46,913)
Net loss attributable to Portola	$ (64,974)	$ (46,913)
Net loss per share attributable to Portola common stockholders:
Basic and diluted	$ (1.15)	$ (0.95)
Shares used to compute net loss per share attributable to Portola common stockholders:
Basic and diluted	56,397,881	49,527,850

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Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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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 consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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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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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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