Purchase Commitments	12 Months Ended
Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Purchase Commitments	7. Purchase Commitments Commercial Supply Agreement (“CSA”) In July 2014, we entered into a CSA with CMC ICOS Biologics, Inc. (“CMC ”), a subsidiary of CMC Biologics S.à.r.l., a privately-held contract manufacturing organization, pursuant to which CMC will manufacture clinical and commercial supply of andexanet alfa. The terms of the CSA required us to purchase an aggregate fixed number of batches of andexanet alfa from CMC beginning in 2015 through 2021. The fixed commitment to purchase batches was divided between two manufacturing lines at CMC: (i) the 2,500 liter manufacturing line which has been used since inception of the program to supply clinical drug product, referred to as “Line A/B”; and (ii) the 6x2,000 liter manufacturing line referred to as “Line C” which was intended to satisfy the drug product requirements of our initial commercial launch. In February 2016, we filed a Biologics License Application (“BLA”) based on the Line A/B manufacturing process and on August 17 2016, we received a Complete Response Letter (“CRL”) from the FDA that focused primarily on Line A/B manufacturing. Given the time and effort required to address the deficiencies raised in the CRL and re-submit the BLA, we made the decision to suspend manufacturing activities on Line C in order to focus on getting andexanet alfa approved using Line A/B. We recorded a charge of $27.3 million in research and development expense in the third quarter of 2016 due to this decision and related uncertainty about whether we would receive future benefits related to advance payments made for Line C manufacturing since inception of the CSA. In December 2016, we entered into an Amended Restated Commercial Supply Agreement (“aCSA”) with CMC that amends and restates the terms of the original CSA. The aCSA increases the number of batches to be manufactured on Line A/B, releases both parties from any obligations related to Line C, and details other services to be provided by CMC to support our regulatory applications in the United States and European Union. Under the aCSA, the batch price is fixed at $1.0 million, and we are required to purchase twenty batches to be manufactured in 2017 and a further ten batches to be manufactured in 2018 contingent upon the successful delivery of specified services in the aCSA. Pursuant to the terms of the aCSA, we received a $33.7 million credit, which may be applied to either satisfy or partially offset specified amounts owed to CMC for services rendered under the aCSA, existing obligations/payables to CMC as of the execution date and future services to be rendered through December 31, 2017. The credit received will have the effect of reducing the cash outlay for 2017 batches by 50% but is not eligible to be applied to the contingent 2018 batches. The term of the aCSA is two years and may be earlier terminated by either party for the other party’s uncured material breach or insolvency. We may terminate the aCSA unilaterally if our applications for regulatory approval for andexanet alfa in the United States and European Union are rejected, for any other safety, efficacy or commercial reasons that lead to the discontinuation, reduction in market demand or commercial infeasibility of andexanet alfa. Under the consolidation guidance, we determined that CMC is a VIE and we are not the primary beneficiary and therefore consolidation of CMC is not required. As of December 31, 2016, we have not provided financial or other support to CMC that was not previously contractually required. We have recorded $1.5 million of accounts payable and $4.0 million of accrued research and development in the consolidated balance sheet as of December 31, 2016. The original CSA and aCSA does not require us to fund operations at CMC and therefore, historically we have quantified our maximum exposure to loss as the aggregate value of prepaid manufacturing services as of each reporting date. Following the charge to research and development expense recorded in the third quarter of 2016, we have no further financial exposure to losses at December 31, 2016. Further, we believe that our total exposure to losses associated with the fixed pricing terms of this agreement is de minimis given the cost per batch, number of batches and time frame over which the batches will be manufactured, pursuant to the amended agreement. Betrixaban Manufacturing Agreement In April 2016, we entered into a Manufacturing Agreement (“the Hovione Agreement”) with Hovione, Limited, (“Hovione”), pursuant to which Hovione will manufacture active pharmaceutical ingredient (“API”) for betrixaban at commercial scale and perform process validation during the term of the agreement. Pursuant to the Hovione Agreement, as amended in September 2016, we have made advance payments of $20.9 million. The unamortized advance payments are recorded as $6.3 million in prepaid research and development and $5.0 million in prepaid and other long-term assets as of December 31, 2016. We will make up to $23.1 million of additional cancellable payments throughout the term of the Hovione Agreement ending June 2018. The additional payments can be cancelled with notice being provided by dates indicated in the Hovione Agreement. Further, if the regulatory approval timeline for betrixaban is delayed for regulatory reasons, there is no cancellation right, however the timing of manufacturing and payments under the Hovione Agreement will be adjusted up to one year to align with such new regulatory approval timeline. The Hovione Agreement may be early terminated by either party for the other party’s uncured material breach or insolvency. Also, we may terminate the Hovione Agreement if the FDA does not approve betrixaban or the regulatory application for betrixaban with the FDA is withdrawn by us or the FDA.

7. Purchase Commitments

Commercial Supply Agreement (“CSA”)

In July 2014, we entered into a CSA with CMC ICOS Biologics, Inc. (“CMC ”), a subsidiary of CMC Biologics S.à.r.l., a privately-held contract manufacturing organization, pursuant to which CMC will manufacture clinical and commercial supply of andexanet alfa. The terms of the CSA required us to purchase an aggregate fixed number of batches of andexanet alfa from CMC beginning in 2015 through 2021. The fixed commitment to purchase batches was divided between two manufacturing lines at CMC: (i) the 2,500 liter manufacturing line which has been used since inception of the program to supply clinical drug product, referred to as “Line A/B”; and (ii) the 6x2,000 liter manufacturing line referred to as “Line C” which was intended to satisfy the drug product requirements of our initial commercial launch.

In February 2016, we filed a Biologics License Application (“BLA”) based on the Line A/B manufacturing process and on August 17 2016, we received a Complete Response Letter (“CRL”) from the FDA that focused primarily on Line A/B manufacturing. Given the time and effort required to address the deficiencies raised in the CRL and re-submit the BLA, we made the decision to suspend manufacturing activities on Line C in order to focus on getting andexanet alfa approved using Line A/B. We recorded a charge of $27.3 million in research and development expense in the third quarter of 2016 due to this decision and related uncertainty about whether we would receive future benefits related to advance payments made for Line C manufacturing since inception of the CSA.

In December 2016, we entered into an Amended Restated Commercial Supply Agreement (“aCSA”) with CMC that amends and restates the terms of the original CSA. The aCSA increases the number of batches to be manufactured on Line A/B, releases both parties from any obligations related to Line C, and details other services to be provided by CMC to support our regulatory applications in the United States and European Union. Under the aCSA, the batch price is fixed at $1.0 million, and we are required to purchase twenty batches to be manufactured in 2017 and a further ten batches to be manufactured in 2018 contingent upon the successful delivery of specified services in the aCSA.

Pursuant to the terms of the aCSA, we received a $33.7 million credit, which may be applied to either satisfy or partially offset specified amounts owed to CMC for services rendered under the aCSA, existing obligations/payables to CMC as of the execution date and future services to be rendered through December 31, 2017. The credit received will have the effect of reducing the cash outlay for 2017 batches by 50% but is not eligible to be applied to the contingent 2018 batches.

The term of the aCSA is two years and may be earlier terminated by either party for the other party’s uncured material breach or insolvency. We may terminate the aCSA unilaterally if our applications for regulatory approval for andexanet alfa in the United States and European Union are rejected, for any other safety, efficacy or commercial reasons that lead to the discontinuation, reduction in market demand or commercial infeasibility of andexanet alfa.

Under the consolidation guidance, we determined that CMC is a VIE and we are not the primary beneficiary and therefore consolidation of CMC is not required. As of December 31, 2016, we have not provided financial or other support to CMC that was not previously contractually required. We have recorded $1.5 million of accounts payable and $4.0 million of accrued research and development in the consolidated balance sheet as of December 31, 2016. The original CSA and aCSA does not require us to fund operations at CMC and therefore, historically we have quantified our maximum exposure to loss as the aggregate value of prepaid manufacturing services as of each reporting date. Following the charge to research and development expense recorded in the third quarter of 2016, we have no further financial exposure to losses at December 31, 2016. Further, we believe that our total exposure to losses associated with the fixed pricing terms of this agreement is de minimis given the cost per batch, number of batches and time frame over which the batches will be manufactured, pursuant to the amended agreement.

Betrixaban Manufacturing Agreement

In April 2016, we entered into a Manufacturing Agreement (“the Hovione Agreement”) with Hovione, Limited, (“Hovione”), pursuant to which Hovione will manufacture active pharmaceutical ingredient (“API”) for betrixaban at commercial scale and perform process validation during the term of the agreement.

Pursuant to the Hovione Agreement, as amended in September 2016, we have made advance payments of $20.9 million. The unamortized advance payments are recorded as $6.3 million in prepaid research and development and $5.0 million in prepaid and other long-term assets as of December 31, 2016. We will make up to $23.1 million of additional cancellable payments throughout the term of the Hovione Agreement ending June 2018. The additional payments can be cancelled with notice being provided by dates indicated in the Hovione Agreement. Further, if the regulatory approval timeline for betrixaban is delayed for regulatory reasons, there is no cancellation right, however the timing of manufacturing and payments under the Hovione Agreement will be adjusted up to one year to align with such new regulatory approval timeline. The Hovione Agreement may be early terminated by either party for the other party’s uncured material breach or insolvency. Also, we may terminate the Hovione Agreement if the FDA does not approve betrixaban or the regulatory application for betrixaban with the FDA is withdrawn by us or the FDA.