Collaborative Arrangements	12 Months Ended
Dec. 31, 2018
Research and Development [Abstract]
Collaborative Arrangements	Collaborative Arrangements Deferred revenue amounts discussed herein as of December 31, 2017 are derived from our Form 10-K for the year ended December 31, 2017. On January 1, 2018 we adopted Topic 606 and subsequently adjusted deferred revenue to give effect to the modified retrospective adoption of the revenue guidance. See Note 3, “Revenue Recognition” for additional information. GSK Platform Technology Transfer, Collaboration and License Agreement In July 2014, we entered into a CodeEvolver^® protein engineering platform technology transfer collaboration and license agreement (the "GSK CodeEvolver^®Agreement") with GlaxoSmithKline ("GSK"). Pursuant to the terms of the agreement, we granted GSK a non-exclusive license to use the CodeEvolver^® protein engineering platform technology to develop novel enzymes for use in the manufacture of GSK's pharmaceutical and health care products. We received an upfront fee upon the execution of the agreement in July 2014 and milestone payments in each of the years from 2014 through April 2016. We completed the transfer of the CodeEvolver^®protein engineering platform technology to GSK in April 2016 and all revenues relating to the technology transfer have been recognized as of April 2016. We have the potential to receive additional cumulative contingent payments that range from $5.75 million to $38.5 million per project based on GSK’s successful application of the licensed technology. We are also eligible to receive royalties based on net sales of GSK’s sales of licensed enzyme products that are currently not being recognized. Merck Platform Technology Transfer and License Agreement In August 2015, we entered into a CodeEvolver^® platform technology transfer collaboration and license agreement (the "Merck CodeEvolver^®Agreement") with Merck, Sharp & Dohme ("Merck") which allows Merck to use the CodeEvolver^®protein engineering technology platform in the field of human and animal healthcare. We received a $5.0 million up-front license fee upon execution of the Merck CodeEvolver^® Agreement, and milestone payments in September 2015 and in September 2016, when we completed the transfer of the engineering platform technology. We recognized research and development revenues of $4.1 million, $3.6 million, and $3.0 million in 2018, 2017 and 2016, respectively, for various research projects under our collaborative arrangement. We have the potential to receive payments of up to a maximum of $15.0 million for each commercial active pharmaceutical ingredient ("API") that is manufactured by Merck using one or more novel enzymes developed by Merck using the CodeEvolver^® protein engineering technology platform. The API payments, which are currently not recognized in revenue, are based on quantity of API developed and manufactured by Merck and will be recognized as usage-based royalties. In October 2018, we entered into an amendment to the Merck CodeEvolver^® Agreement whereby we amended certain licensing provisions and one exhibit. In January 2019, we entered into an amendment to the Merck CodeEvolver^® Agreement whereby we will install certain CodeEvolver^®protein engineering technology upgrades into Merck’s platform license installation and maintain those upgrades for a multi-year term. Merck Sitagliptin Catalyst Supply Agreement In February 2012, we entered into a five-year Sitagliptin Catalyst Supply Agreement (“Sitagliptin Catalyst Supply Agreement”) with Merck whereby Merck may obtain commercial scale enzyme for use in the manufacture of Januvia^®, its product based on the active ingredient Sitagliptin. In December 2015, Merck exercised its option under the terms of the Sitagliptin Catalyst Supply Agreement to extend the agreement for an additional five years through February 2022. Effective as of January 2016, we and Merck amended the Sitagliptin Catalyst Supply Agreement to prospectively provide for variable pricing based on the cumulative volume of sitagliptin catalyst purchased by Merck and to allow Merck to purchase a percentage of its requirements for sitagliptin catalyst from a specified third-party supplier. Merck received a distinct, functional license to manufacture a portion of its demand beginning January 1, 2018, which we recognized as research and development revenue. We recognized research and development revenues of $1.3 million, $1.3 million and $1.3 million in 2018, 2017 and 2016, respectively. In June 2017, we completed a contractual milestone by qualifying the specified third-party enzyme supplier and recognized $0.3 million as research and development revenues. We have determined that the variable pricing, which provides a discount based on the cumulative volume of sitagliptin catalyst purchased by Merck, provides Merck material rights and we are recognizing product revenues using the alternative method. Under the alternative approach, we estimate the total expected consideration and allocate it proportionately with the expected sales. The Sitagliptin Catalyst Supply Agreement requires Merck to pay an annual fee for the rights to the sitagliptin technology each year for the term of the Sitagliptin Catalyst Supply Agreement. Amounts of annual license fees are based on contractually agreed prices and are on a declining scale over the term of the contract. We had a deferred revenue balance from Merck of $3.6 million at December 31, 2018 and $1.5 million at December 31, 2017. Pursuant to the terms of the Sitagliptin Catalyst Supply Agreement, Merck may purchase supply from us for a fee based on contractually stated prices and we recognized $12.3 million, $9.0 million and $5.9 million in 2018, 2017 and 2016, respectively, in product revenue under this agreement. Enzyme Supply Agreement In November 2016, we entered into a supply agreement whereby our customer may purchase quantities of one of our proprietary enzymes for use in its commercial manufacture of a product. Pursuant to the supply agreement, we received an upfront payment of $0.8 million in December 2016, which we accordingly recorded as deferred revenues. Such upfront payment will be recognized over the period of the supply agreement as the customer purchases our proprietary enzyme. We additionally have determined that the volume discounts under the supply agreement provides the customer material rights and we are recognizing revenues using the alternative method. As of December 31, 2018 and 2017, we had deferred revenue from the supply agreement of $2.0 million and $0.7 million, respectively. Research and Development Agreement In March 2017, we entered into a multi-year research and development services agreement with Tate & Lyle Ingredients Americas LLC ("Tate & Lyle") to develop enzymes for use in the manufacture of Tate & Lyle’s zero-calorie TASTEVA^® M Stevia sweetener. Under the agreement, we received an upfront payment of $3.0 million, which was originally recognized ratably over the maximum term of the services period of 21 months. Beginning January 1, 2018, we are recognizing revenue using a single measure of progress that depicts our performance in transferring the services. During the second quarter of 2018, Tate & Lyle opted to obtain additional development services that we completed by June 30, 2018 and we earned milestone payments upon completion of the services. We recognized $7.1 million and $3.2 million of revenue in 2018 and 2017, respectively, for research and development services under the research and development agreement. As of December 31, 2018 and 2017, we had deferred revenue from the development services agreement of zero and $3.1 million, respectively. Global Development, Option and License Agreement and Strategic Collaboration Agreement In October 2017, we entered into a Global Development, Option and License Agreement (the "Nestlé Agreement") with Nestec Ltd. ("Nestlé Health Science") and, solely for the purpose of the integration and the dispute resolution clauses of the Nestlé Agreement, Nestlé Health Science S.A., to advance CDX-6114, our enzyme biotherapeutic product candidate for the potential treatment of PKU. We received an upfront cash payment of $14.0 million in 2017 upon the execution of the Nestlé Agreement and a $4.0 million milestone payment 60 days after dosing the first subjects in a first-in-human Phase 1a dose-escalation trial with CDX-6114 for the potential treatment of PKU. The $4.0 million milestone payment that was triggered by the initiation of the trial was received in September 2018. The upfront payment and the variable consideration relating to the progress payment of $4.0 million are being recognized over time as the development work is being performed. Revenue is being recognized using a single measure of progress that depicts our performance in transferring control of the services, which is based on the ratio of level of effort incurred to date compared to the total estimated level of effort required to complete all performance obligations under the agreement. We recognized development fees of $9.9 million in 2018 as research and development revenue and $7.2 million in 2017. We had deferred revenue related to the development fees attributed to the milestone payment and up-front fees of $1.9 million at December 31, 2018 and $6.8 million at December 31, 2017. In December 2018, Nestlé Health Science became obligated to pay us an additional $1.0 million within 60 days after the achievement of a milestone relating to formulation of CDX-6114. In January 2019, we received notice from the U.S. Food and Drug Administration (the “FDA”) that it had completed its review of our investigational new drug application (“IND”) for CDX-6114 and concluded that we may proceed with the proposed Phase 1b multiple ascending dose study in healthy volunteers in the United States. In February 2019, Nestlé Health Science exercised its option to obtain an exclusive, worldwide, royalty-bearing, sub-licensable license for the global development and commercialization of CDX-6114 for the management of PKU. As a result of the option exercise, Nestlé Health Science is obligated to pay us $3.0 million within 60 days after exercise of the option. Upon exercising its option, Nestlé Health Science has assumed all responsibilities for future clinical development and commercialization of CDX-6114, with the exception of the completion of an extension study, CDX - 6114-004, which is expected to be completed in the second quarter of 2019. See Note 16, “Subsequent Events” in the notes to the Consolidated Financial Statements set forth in Item 8 of this Annual Report on Form 10-K for details. Other potential payments from Nestlé Health Science to us under the Nestlé Agreement include (i) development and approval milestones of up to $86.0 million, (ii) sales-based milestones of up to $250.0 million in the aggregate, which aggregate amount is achievable if net sales exceed $1.0 billion in a single year, and (iii) tiered royalties, at percentages ranging from the middle single digits to low double-digits, of net sales of Product. In addition to the Nestlé Agreement, we and Nestlé Health Science concurrently entered into a Strategic Collaboration Agreement (the “Strategic Collaboration Agreement”) pursuant to which we and Nestlé Health Science will collaborate to leverage the CodeEvolver^® protein engineering technology platform to develop novel enzymes for Nestlé Health Science’s established Consumer Care and Medical Nutrition business areas. Under the Strategic Collaboration Agreement, we received an upfront payment of $1.2 million in 2017 and an incremental $0.6 million payment in September 2018 for additional services. We recognized research and development fees of $3.6 million and $0.5 million in 2018 and 2017, respectively. As of December 31, 2018 and 2017, we had deferred revenue of $0.8 million and $1.1 million, respectively. Strategic Collaboration Agreement In April 2018, we entered into the Porton Agreement with Porton to license key elements of Codexis’ biocatalyst technology for use in Porton’s global custom intermediate and API development and manufacturing business. Under the Porton Agreement, we are eligible to receive annual collaboration fees and research and development revenues. We have the potential to receive performance payments based on products produced by Porton using our company technology under the license agreement. We received an initial collaboration fee of $0.5 million within 30 days of the effective date of the agreement. As of December 31, 2018, we completed the technical transfer and we recognized revenue of $2.8 million in 2018 as research and development revenue. Revenue relating to the functional license provided to Porton was recognized at a point in time when control of the license transferred to the customer.

Collaborative Arrangements

Deferred revenue amounts discussed herein as of December 31, 2017 are derived from our Form 10-K for the year ended December 31, 2017. On January 1, 2018 we adopted Topic 606 and subsequently adjusted deferred revenue to give effect to the modified retrospective adoption of the revenue guidance. See Note 3, “Revenue Recognition” for additional information.

GSK Platform Technology Transfer, Collaboration and License Agreement

In July 2014, we entered into a CodeEvolver^® protein engineering platform technology transfer collaboration and license agreement (the "GSK CodeEvolver^®Agreement") with GlaxoSmithKline ("GSK"). Pursuant to the terms of the agreement, we granted GSK a non-exclusive license to use the CodeEvolver^® protein engineering platform technology to develop novel enzymes for use in the manufacture of GSK's pharmaceutical and health care products.

We received an upfront fee upon the execution of the agreement in July 2014 and milestone payments in each of the years from 2014 through April 2016. We completed the transfer of the CodeEvolver^®protein engineering platform technology to GSK in April 2016 and all revenues relating to the technology transfer have been recognized as of April 2016. We have the potential to receive additional cumulative contingent payments that range from $5.75 million to $38.5 million per project based on GSK’s successful application of the licensed technology. We are also eligible to receive royalties based on net sales of GSK’s sales of licensed enzyme products that are currently not being recognized.

Merck Platform Technology Transfer and License Agreement

In August 2015, we entered into a CodeEvolver^® platform technology transfer collaboration and license agreement (the "Merck CodeEvolver^®Agreement") with Merck, Sharp & Dohme ("Merck") which allows Merck to use the CodeEvolver^®protein engineering technology platform in the field of human and animal healthcare.

We received a $5.0 million up-front license fee upon execution of the Merck CodeEvolver^® Agreement, and milestone payments in September 2015 and in September 2016, when we completed the transfer of the engineering platform technology. We recognized research and development revenues of $4.1 million, $3.6 million, and $3.0 million in 2018, 2017 and 2016, respectively, for various research projects under our collaborative arrangement.

We have the potential to receive payments of up to a maximum of $15.0 million for each commercial active pharmaceutical ingredient ("API") that is manufactured by Merck using one or more novel enzymes developed by Merck using the CodeEvolver^® protein engineering technology platform. The API payments, which are currently not recognized in revenue, are based on quantity of API developed and manufactured by Merck and will be recognized as usage-based royalties.

In October 2018, we entered into an amendment to the Merck CodeEvolver^® Agreement whereby we amended certain licensing provisions and one exhibit. In January 2019, we entered into an amendment to the Merck CodeEvolver^® Agreement whereby we will install certain CodeEvolver^®protein engineering technology upgrades into Merck’s platform license installation and maintain those upgrades for a multi-year term.

Merck Sitagliptin Catalyst Supply Agreement

In February 2012, we entered into a five-year Sitagliptin Catalyst Supply Agreement (“Sitagliptin Catalyst Supply Agreement”) with Merck whereby Merck may obtain commercial scale enzyme for use in the manufacture of Januvia^®, its product based on the active ingredient Sitagliptin. In December 2015, Merck exercised its option under the terms of the Sitagliptin Catalyst Supply Agreement to extend the agreement for an additional five years through February 2022.

Effective as of January 2016, we and Merck amended the Sitagliptin Catalyst Supply Agreement to prospectively provide for variable pricing based on the cumulative volume of sitagliptin catalyst purchased by Merck and to allow Merck to purchase a percentage of its requirements for sitagliptin catalyst from a specified third-party supplier. Merck received a distinct, functional license to manufacture a portion of its demand beginning January 1, 2018, which we recognized as research and development revenue. We recognized research and development revenues of $1.3 million, $1.3 million and $1.3 million in 2018, 2017 and 2016, respectively.

In June 2017, we completed a contractual milestone by qualifying the specified third-party enzyme supplier and recognized $0.3 million as research and development revenues.

We have determined that the variable pricing, which provides a discount based on the cumulative volume of sitagliptin catalyst purchased by Merck, provides Merck material rights and we are recognizing product revenues using the alternative method. Under the alternative approach, we estimate the total expected consideration and allocate it proportionately with the expected sales.

The Sitagliptin Catalyst Supply Agreement requires Merck to pay an annual fee for the rights to the sitagliptin technology each year for the term of the Sitagliptin Catalyst Supply Agreement. Amounts of annual license fees are based on contractually agreed prices and are on a declining scale over the term of the contract.

We had a deferred revenue balance from Merck of $3.6 million at December 31, 2018 and $1.5 million at December 31, 2017. Pursuant to the terms of the Sitagliptin Catalyst Supply Agreement, Merck may purchase supply from us for a fee based on contractually stated prices and we recognized $12.3 million, $9.0 million and $5.9 million in 2018, 2017 and 2016, respectively, in product revenue under this agreement.

Enzyme Supply Agreement

In November 2016, we entered into a supply agreement whereby our customer may purchase quantities of one of our proprietary enzymes for use in its commercial manufacture of a product. Pursuant to the supply agreement, we received an upfront payment of $0.8 million in December 2016, which we accordingly recorded as deferred revenues. Such upfront payment will be recognized over the period of the supply agreement as the customer purchases our proprietary enzyme. We additionally have determined that the volume discounts under the supply agreement provides the customer material rights and we are recognizing revenues using the alternative method. As of December 31, 2018 and 2017, we had deferred revenue from the supply agreement of $2.0 million and $0.7 million, respectively.

Research and Development Agreement

In March 2017, we entered into a multi-year research and development services agreement with Tate & Lyle Ingredients Americas LLC ("Tate & Lyle") to develop enzymes for use in the manufacture of Tate & Lyle’s zero-calorie TASTEVA^® M Stevia sweetener. Under the agreement, we received an upfront payment of $3.0 million, which was originally recognized ratably over the maximum term of the services period of 21 months. Beginning January 1, 2018, we are recognizing revenue using a single measure of progress that depicts our performance in transferring the services. During the second quarter of 2018, Tate & Lyle opted to obtain additional development services that we completed by June 30, 2018 and we earned milestone payments upon completion of the services. We recognized $7.1 million and $3.2 million of revenue in 2018 and 2017, respectively, for research and development services under the research and development agreement. As of December 31, 2018 and 2017, we had deferred revenue from the development services agreement of zero and $3.1 million, respectively.

Global Development, Option and License Agreement and Strategic Collaboration Agreement

In October 2017, we entered into a Global Development, Option and License Agreement (the "Nestlé Agreement") with Nestec Ltd. ("Nestlé Health Science") and, solely for the purpose of the integration and the dispute resolution clauses of the Nestlé Agreement, Nestlé Health Science S.A., to advance CDX-6114, our enzyme biotherapeutic product candidate for the potential treatment of PKU.

We received an upfront cash payment of $14.0 million in 2017 upon the execution of the Nestlé Agreement and a $4.0 million milestone payment 60 days after dosing the first subjects in a first-in-human Phase 1a dose-escalation trial with CDX-6114 for the potential treatment of PKU. The $4.0 million milestone payment that was triggered by the initiation of the trial was received in September 2018. The upfront payment and the variable consideration relating to the progress payment of $4.0 million are being recognized over time as the development work is being performed. Revenue is being recognized using a single measure of progress that depicts our performance in transferring control of the services, which is based on the ratio of level of effort incurred to date compared to the total estimated level of effort required to complete all performance obligations under the agreement. We recognized development fees of $9.9 million in 2018 as research and development revenue and $7.2 million in 2017. We had deferred revenue related to the development fees attributed to the milestone payment and up-front fees of $1.9 million at December 31, 2018 and $6.8 million at December 31, 2017.

In December 2018, Nestlé Health Science became obligated to pay us an additional $1.0 million within 60 days after the achievement of a milestone relating to formulation of CDX-6114. In January 2019, we received notice from the U.S. Food and Drug Administration (the “FDA”) that it had completed its review of our investigational new drug application (“IND”) for CDX-6114 and concluded that we may proceed with the proposed Phase 1b multiple ascending dose study in healthy volunteers in the United States. In February 2019, Nestlé Health Science exercised its option to obtain an exclusive, worldwide, royalty-bearing, sub-licensable license for the global development and commercialization of CDX-6114 for the management of PKU. As a result of the option exercise, Nestlé Health Science is obligated to pay us $3.0 million within 60 days after exercise of the option. Upon exercising its option, Nestlé Health Science has assumed all responsibilities for future clinical development and commercialization of CDX-6114, with the exception of the completion of an extension study, CDX - 6114-004, which is expected to be completed in the second quarter of 2019. See Note 16, “Subsequent Events” in the notes to the Consolidated Financial Statements set forth in Item 8 of this Annual Report on Form 10-K for details. Other potential payments from Nestlé Health Science to us under the Nestlé Agreement include (i) development and approval milestones of up to $86.0 million, (ii) sales-based milestones of up to $250.0 million in the aggregate, which aggregate amount is achievable if net sales exceed $1.0 billion in a single year, and (iii) tiered royalties, at percentages ranging from the middle single digits to low double-digits, of net sales of Product.

In addition to the Nestlé Agreement, we and Nestlé Health Science concurrently entered into a Strategic Collaboration Agreement (the “Strategic Collaboration Agreement”) pursuant to which we and Nestlé Health Science will collaborate to leverage the CodeEvolver^® protein engineering technology platform to develop novel enzymes for Nestlé Health Science’s established Consumer Care and Medical Nutrition business areas. Under the Strategic Collaboration Agreement, we received an upfront payment of $1.2 million in 2017 and an incremental $0.6 million payment in September 2018 for additional services. We recognized research and development fees of $3.6 million and $0.5 million in 2018 and 2017, respectively. As of December 31, 2018 and 2017, we had deferred revenue of $0.8 million and $1.1 million, respectively.

Strategic Collaboration Agreement

In April 2018, we entered into the Porton Agreement with Porton to license key elements of Codexis’ biocatalyst technology for use in Porton’s global custom intermediate and API development and manufacturing business. Under the Porton Agreement, we are eligible to receive annual collaboration fees and research and development revenues. We have the potential to receive performance payments based on products produced by Porton using our company technology under the license agreement. We received an initial collaboration fee of $0.5 million within 30 days of the effective date of the agreement. As of December 31, 2018, we completed the technical transfer and we recognized revenue of $2.8 million in 2018 as research and development revenue. Revenue relating to the functional license provided to Porton was recognized at a point in time when control of the license transferred to the customer.