Asset Acquisition and License Agreements	12 Months Ended
Dec. 31, 2016
Research And Development [Abstract]
Asset Acquisition and License Agreements	8. Asset Acquisition and License Agreements Agreement SRX Cardio, LLC (“SRX Cardio”) In December 2015, we entered into an option agreement with SRX Cardio to explore a novel approach to develop a drug in the field of hypercholesterolemia. This agreement provided us an option to enter into an exclusive license agreement as well as responsibility to lead and fund the development effort during the option period. In September 2016, we exercised our right to enter into an exclusive license agreement. Pursuant to the terms of the agreement, we made an upfront payment of $2.2 million to acquire the license and are obligated to pay up to $152.5 million in research and development milestones related to the advancement of the program and royalties in the range of 2% to 6% of worldwide net sales. We may terminate the license agreement upon 90 days notice for convenience and the agreement may also be terminated by either party for a material breach by the other party. We determined that SRX Cardio is and continues to be a variable interest entity and that we hold a variable interest in SRX Cardio’s intellectual property assets and the related potential future product candidates these assets may produce. Due to the absence of other significant development programs at SRX Cardio, we concluded that the variable interest was in the entity as a whole. Given the stage of development, we concluded that SRX Cardio is not considered a business as they lack the processes required to generate outputs. We concluded that the responsibilities assigned to us under the option agreement and as continued via the exclusive license agreement provided us control over those activities most significant to SRX Cardio, and therefore we are considered to be the primary beneficiary of SRX Cardio. Accordingly, SRX Cardio is subject to consolidation and we have consolidated the financial statements of SRX Cardio since inception of the agreement on December 1, 2015 by (a) eliminating all intercompany balances and transactions; and (b) allocating income or loss attributable to the noncontrolling interest in SRX Cardio to net income or loss attributable to noncontrolling interest in our consolidated statement of operations and reflecting noncontrolling interest on our consolidated balance sheet. Our interest in SRX Cardio is limited to the development of the intellectual property asset. The upfront payments of $500,000 and $2.2 million and the obligation to fund the development plan represent our maximum exposure to loss under the agreement. We did not acquire any equity interest in SRX Cardio, any interest in SRX Cardio's cash and cash equivalents or any control over their activities that do not relate to the exclusive license agreement. SRX Cardio does not have any right to the Company's assets except as provided in the exclusive license agreement. At the inception of the agreement, the identifiable assets, assumed liabilities and non-controlling interest of SRX Cardio were recorded at their estimated fair value upon the initial consolidation of SRX Cardio, including the in-process research and development intangible asset. We estimated the fair value of these indefinite lived intangible assets to be $3.2 million and the noncontrolling interest to be $2.9 million. The fair value was estimated using present-value models on potential contingent milestones and royalty payments (“contingent future payments”), based on assumptions regarding the probability of achieving the development milestones, estimate of time to develop the drug candidate, estimates of future cash flows from potential product sales and assumptions regarding the appropriate discount rate. As of December 31, 2016, we have not provided financial or other support to SRX Cardio that was not previously contracted or required. We recorded SRX Cardio’s $178,000 of cash as restricted cash because (a) we do not have any interest in or control over SRX Cardio's cash and (b) the agreement does not provide for these assets to be used for the development of the intellectual property assets developed pursuant to this agreement. We recorded $930,000 as net income attributable to noncontrolling interest (SRX Cardio) on our consolidated statements of operations, reflecting SRX Cardio’s net income for the reporting period after adjusting for the decrease in fair value of contingent future payments. For the year ended December 31, 2016, the fair value of contingent future payments decreased by $870,000 primarily due to changes in our estimated development timeline and market interest rates. Should the development program make substantive advancement, we expect to record increases in the fair value of the contingent milestone and royalty payments with a corresponding increase to net loss or decrease to net income attributable to Portola Shareholders. Millennium Pharmaceuticals, Inc. (“Millennium”) In August 2004, we entered into an agreement to license from Millennium certain exclusive rights to research, develop and commercialize certain compounds that inhibit Factor Xa, including betrixaban. The license agreement requires us to make license fee, milestone, royalty and sublicense sharing payments to Millennium as we develop, commercialize or sublicense betrixaban. The license agreement will continue in force, on a country-by-country basis, until the expiration of the relevant patents or ten years after the launch, whichever is later, or termination by either party pursuant to the agreement. This license agreement may be terminated by either party for the other party’s uncured material breach. In addition, we may terminate this agreement for convenience with 30 days’ advance written notice. Under the agreement, milestone payments are determined based on the indication included in our filing and become payable upon acceptance of our NDA and regulatory approval in the United States and Europe. In December 2016, the FDA accepted our NDA for betrixaban for extended-duration prophylaxis of venous thromboembolism, triggering a $2.0 million milestone payment to Millennium which is recorded as a research and development expense in the consolidated statement of operations. Should betrixaban receive approval in the United States and/or Europe, another $5.0 million will become payable for each such approval event and a tiered single-digit royalty rate would apply to net product sales thereafter. A further $23.0 million in milestone payments would become due if betrixaban was approved for other indications specified in the agreement in the United States and Europe. Astellas Pharma, Inc. (“Astellas”) In December 2010, we amended and restated the original license agreement with Astellas executed in August 2005. The amended and restated license agreement provides us certain exclusive rights to research, develop and commercialize Syk inhibitors. Pursuant to the agreement, we may be required to pay Astellas up to $71.5 million in milestone payments upon the achievement of certain regulatory, approval and sales events for each Syk inhibitor we develop. Additionally, in the event that we enter into an agreement with a third party to develop and commercialize Syk inhibitors, we would be required to pay Astellas 20% of any payments (excluding royalties) received under the collaboration. These payments would be creditable against the aforementioned milestone payments. In addition, we are required to pay Astellas royalties for worldwide sales for any commercial Syk inhibitor product. In December 2016, we out-licensed exclusive rights to cerdulatinb in topical formulation, excluding oncology, to Dermavant Sciences GmbH (“Dermavant”). Twenty percent of the upfront payment received from Dermavant, $1.8 million, is payable to Astellas and was recorded to research and development expense in the consolidated statement of operations for the period ended December 31, 2016.

8. Asset Acquisition and License Agreements

Agreement SRX Cardio, LLC (“SRX Cardio”)

In December 2015, we entered into an option agreement with SRX Cardio to explore a novel approach to develop a drug in the field of hypercholesterolemia. This agreement provided us an option to enter into an exclusive license agreement as well as responsibility to lead and fund the development effort during the option period.

In September 2016, we exercised our right to enter into an exclusive license agreement. Pursuant to the terms of the agreement, we made an upfront payment of $2.2 million to acquire the license and are obligated to pay up to $152.5 million in research and development milestones related to the advancement of the program and royalties in the range of 2% to 6% of worldwide net sales. We may terminate the license agreement upon 90 days notice for convenience and the agreement may also be terminated by either party for a material breach by the other party.

We determined that SRX Cardio is and continues to be a variable interest entity and that we hold a variable interest in SRX Cardio’s intellectual property assets and the related potential future product candidates these assets may produce. Due to the absence of other significant development programs at SRX Cardio, we concluded that the variable interest was in the entity as a whole. Given the stage of development, we concluded that SRX Cardio is not considered a business as they lack the processes required to generate outputs.

We concluded that the responsibilities assigned to us under the option agreement and as continued via the exclusive license agreement provided us control over those activities most significant to SRX Cardio, and therefore we are considered to be the primary beneficiary of SRX Cardio. Accordingly, SRX Cardio is subject to consolidation and we have consolidated the financial statements of SRX Cardio since inception of the agreement on December 1, 2015 by (a) eliminating all intercompany balances and transactions; and (b) allocating income or loss attributable to the noncontrolling interest in SRX Cardio to net income or loss attributable to noncontrolling interest in our consolidated statement of operations and reflecting noncontrolling interest on our consolidated balance sheet. Our interest in SRX Cardio is limited to the development of the intellectual property asset. The upfront payments of $500,000 and $2.2 million and the obligation to fund the development plan represent our maximum exposure to loss under the agreement. We did not acquire any equity interest in SRX Cardio, any interest in SRX Cardio's cash and cash equivalents or any control over their activities that do not relate to the exclusive license agreement. SRX Cardio does not have any right to the Company's assets except as provided in the exclusive license agreement.

At the inception of the agreement, the identifiable assets, assumed liabilities and non-controlling interest of SRX Cardio were recorded at their estimated fair value upon the initial consolidation of SRX Cardio, including the in-process research and development intangible asset. We estimated the fair value of these indefinite lived intangible assets to be $3.2 million and the noncontrolling interest to be $2.9 million. The fair value was estimated using present-value models on potential contingent milestones and royalty payments (“contingent future payments”), based on assumptions regarding the probability of achieving the development milestones, estimate of time to develop the drug candidate, estimates of future cash flows from potential product sales and assumptions regarding the appropriate discount rate.

As of December 31, 2016, we have not provided financial or other support to SRX Cardio that was not previously contracted or required. We recorded SRX Cardio’s $178,000 of cash as restricted cash because (a) we do not have any interest in or control over SRX Cardio's cash and (b) the agreement does not provide for these assets to be used for the development of the intellectual property assets developed pursuant to this agreement. We recorded $930,000 as net income attributable to noncontrolling interest (SRX Cardio) on our consolidated statements of operations, reflecting SRX Cardio’s net income for the reporting period after adjusting for the decrease in fair value of contingent future payments. For the year ended December 31, 2016, the fair value of contingent future payments decreased by $870,000 primarily due to changes in our estimated development timeline and market interest rates. Should the development program make substantive advancement, we expect to record increases in the fair value of the contingent milestone and royalty payments with a corresponding increase to net loss or decrease to net income attributable to Portola Shareholders.

Millennium Pharmaceuticals, Inc. (“Millennium”)

In August 2004, we entered into an agreement to license from Millennium certain exclusive rights to research, develop and commercialize certain compounds that inhibit Factor Xa, including betrixaban. The license agreement requires us to make license fee, milestone, royalty and sublicense sharing payments to Millennium as we develop, commercialize or sublicense betrixaban. The license agreement will continue in force, on a country-by-country basis, until the expiration of the relevant patents or ten years after the launch, whichever is later, or termination by either party pursuant to the agreement. This license agreement may be terminated by either party for the other party’s uncured material breach. In addition, we may terminate this agreement for convenience with 30 days’ advance written notice.

Under the agreement, milestone payments are determined based on the indication included in our filing and become payable upon acceptance of our NDA and regulatory approval in the United States and Europe. In December 2016, the FDA accepted our NDA for betrixaban for extended-duration prophylaxis of venous thromboembolism, triggering a $2.0 million milestone payment to Millennium which is recorded as a research and development expense in the consolidated statement of operations. Should betrixaban receive approval in the United States and/or Europe, another $5.0 million will become payable for each such approval event and a tiered single-digit royalty rate would apply to net product sales thereafter.

A further $23.0 million in milestone payments would become due if betrixaban was approved for other indications specified in the agreement in the United States and Europe.

Astellas Pharma, Inc. (“Astellas”)

In December 2010, we amended and restated the original license agreement with Astellas executed in August 2005. The amended and restated license agreement provides us certain exclusive rights to research, develop and commercialize Syk inhibitors. Pursuant to the agreement, we may be required to pay Astellas up to $71.5 million in milestone payments upon the achievement of certain regulatory, approval and sales events for each Syk inhibitor we develop. Additionally, in the event that we enter into an agreement with a third party to develop and commercialize Syk inhibitors, we would be required to pay Astellas 20% of any payments (excluding royalties) received under the collaboration. These payments would be creditable against the aforementioned milestone payments. In addition, we are required to pay Astellas royalties for worldwide sales for any commercial Syk inhibitor product.

In December 2016, we out-licensed exclusive rights to cerdulatinb in topical formulation, excluding oncology, to Dermavant Sciences GmbH (“Dermavant”). Twenty percent of the upfront payment received from Dermavant, $1.8 million, is payable to Astellas and was recorded to research and development expense in the consolidated statement of operations for the period ended December 31, 2016.