Collaborative Arrangements	9 Months Ended
Sep. 30, 2016
Research and Development [Abstract]
Collaborative Arrangements	Collaborative Arrangements GSK Platform Technology Transfer, Collaboration and License Agreement In July 2014, we entered into a CodeEvolver^® platform technology transfer collaboration and license agreement (the “GSK CodeEvolver^®Agreement”) with GSK. Pursuant to the terms of the agreement, we granted GSK a non-exclusive license to use the CodeEvolver^® protein engineering technology platform to develop novel enzymes for use in the manufacture of GSK's pharmaceutical and health care products. We received a $6.0 million up-front licensing fee upon signing the GSK CodeEvolver^® Agreement and subsequently a $5.0 million non-creditable, non-refundable milestone payment upon achievement of the first milestone in 2014. In September 2015, we achieved the second milestone of the agreement and earned milestone revenue of $6.5 million. In April 2016, we completed the full transfer of the CodeEvolver^®protein engineering platform technology and earned milestone revenue of $7.5 million, for which payment was received in June 2016. We also have the potential to receive additional contingent payments that range from $5.75 million to $38.5 million per project based on GSK's successful application of the licensed technology. The contingent payments are not deemed substantive milestones due to the fact that the achievement of the event underlying the payment predominantly relates to GSK's performance of future development and commercialization activities. We are eligible to receive royalties based on net sales, if any, of a limited set of products developed by GSK using the CodeEvolver® protein engineering technology platform. The term of the GSK CodeEvolver^® Agreement continues, unless earlier terminated, until the expiration of all payment obligations under the GSK CodeEvolver^® Agreement. GSK can terminate the GSK CodeEvolver^® Agreement by providing 90 days written notice to us. Under the GSK CodeEvolver^®Agreement, the significant deliverables were determined to be the license, platform technology transfer, and contingent obligation to supply GSK with enzymes manufactured by us at GSK’s expense. We determined that the license did not have stand-alone value. In addition, we determined that the license and the platform technology transfer and our participation in joint steering committee activities in connection with the platform technology transfer represent a single unit of accounting. Our participation in the joint steering committee does not represent a separate unit of accounting because GSK could not negotiate for and/or acquire these services from other third parties and our participation on the joint steering committee is coterminous with the technology transfer period. Amounts to be received under the supply arrangement, if any, described above will be recognized as revenue to the extent GSK purchases enzymes from us. The up-front license fee of $6.0 million was being recognized ratably over the technology transfer period of three years since July 2014. As the technology transfer was completed earlier than anticipated, we recognized license fees of $0 and $3.0 million for the three and nine months ended September 30, 2016, respectively, compared to $0.5 million and $1.5 million for the three and nine months ended September 30, 2015, respectively, as biocatalyst research and development revenues. We had a deferred revenue balance from GSK related to the upfront license fee of $0 at September 30, 2016 and $3.0 million at December 31, 2015. In September 2016, we recorded our first project-specific contingent fee based on GSK's successful application of our technology in an existing pharmaceutical product. Merck Platform Technology Transfer and License Agreement In August 2015, we entered into a CodeEvolver^® platform technology transfer and license agreement (the "Merck CodeEvolver^® Agreement") with Merck. The Merck CodeEvolver^®Agreement 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, which is being recognized ratably over the estimated platform technology transfer period of two years. In September 2015, we achieved the first milestone under the Merck CodeEvolver^® Agreement and earned milestone revenue of $5.0 million. In September 2016, we completed the full transfer of the engineering platform technology and earned milestone revenue of $8.0 million. We received the $8.0 million milestone payment in the fourth quarter of 2016. Following the completion of the technology transfer, we may be eligible 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. Under the terms of the Merck CodeEvolver^®Agreement, we granted to Merck a non-exclusive worldwide license to use the CodeEvolver^® protein engineering technology platform to research, develop and manufacture novel enzymes for use by Merck in its internal research programs ("Merck Non-Exclusive Field"). The license to Merck is exclusive for the research, development and manufacture of novel enzymes for use by Merck in the chemical synthesis of therapeutic products owned or controlled by Merck ("Merck Exclusive Field"). Merck has the right to grant sublicenses to affiliates of Merck and, in certain limited circumstances, to third parties. We also granted to Merck a license to make or have made products manufactured using the CodeEvolver^® protein engineering technology platform with a right to grant sublicenses solely to affiliates of Merck, contract manufacturing organizations and contract research organizations. The manufacturing license is exclusive in the Merck Exclusive Field and non-exclusive in the Merck Non-Exclusive Field. The licenses are subject to certain limitations based on pre-existing contractual obligations that apply to the technology and intellectual property that are the subject of the license grants. The licenses do not permit the use of the CodeEvolver^® protein engineering technology platform to discover any therapeutic enzyme, diagnostic product or vaccine. In addition, Merck is prohibited from using the CodeEvolver^® protein engineering technology platform to develop or produce enzymes or any other compounds for or on behalf of any third parties except in a very limited manner when Merck divests a therapeutic product that is manufactured using an enzyme developed using the CodeEvolver^® protein engineering technology platform. Under the Merck CodeEvolver^® Agreement, we transferred the CodeEvolver^® protein engineering technology platform to Merck over the period from August 2015 through September 2016. As part of this technology transfer, we provided to Merck our proprietary enzymes, proprietary protein engineering protocols and methods, and proprietary software algorithms. We are providing additional enzyme evolution services to Merck at our laboratories in Redwood City through November 2016. The remaining deferred revenue relating to the upfront payment will be recognized upon completion of the additional enzyme evolution services. The licenses to Merck are granted under patents, patent applications and know-how that we own or control as of the effective date of the Merck CodeEvolver^® Agreementand that cover the CodeEvolver^® protein engineering technology platform. Any improvements to the CodeEvolver^® protein engineering technology platform during the technology transfer period are also included in the license grants from Codexis to Merck. Following the technology transfer period, Merck can exercise annual options that, upon payment of certain option fees, would extend Merck's license to include certain improvements to the CodeEvolver^® protein engineering technology platform that arise during the three-year period that begins at the end of the technology transfer period. Under the Merck CodeEvolver^® Agreement, we will own any improvements to our protein engineering methods, processes and algorithms that arise and any enzyme technology or process technology that are developed during a technology transfer project, an evolution program or additional services. Merck will own (the "Merck-Owned Technology") (a) any enzyme technology that is developed solely by Merck under the Merck CodeEvolver^® Agreement using the CodeEvolver^® protein engineering technology platform (a "Project Enzyme") and (b) the methods of use of any Project Enzyme or any enzyme developed jointly by Merck and us using the CodeEvolver^® protein engineering technology platform. Merck granted to us a worldwide, non-exclusive, fully paid-up, royalty-free license, with the right to grant sublicenses, to use the Merck-Owned Technology outside of the Merck Exclusive Field. For each API that Merck manufactures using an enzyme developed with the CodeEvolver^®protein engineering technology platform, we will have a right of first refusal to supply Merck with the enzyme used to manufacture the API if Merck outsources the supply of the enzyme. Our right of first refusal applies during the period that begins on the completion of a phase III clinical trial for the product containing the API and ends five years following regulatory approval for such product. The Merck CodeEvolver^® Agreement has a term that continues, unless earlier terminated, until the expiration of all payment obligations under the agreement. Merck may terminate the Merck CodeEvolver^® Agreement by providing 90 days written notice to us. We can terminate the Merck CodeEvolver^® Agreement by providing 30 days written notice to Merck if we determine, pursuant to our contractual audit rights under the Merck CodeEvolver^® Agreement, that Merck has repeatedly failed to make required payments to us and/or materially underpaid us an amount due under the Merck CodeEvolver^® Agreement. In the event the Merck CodeEvolver^® Agreement is terminated earlier by Merck, or by us due to an uncured material breach by Merck, or if Merck sells or transfers to a third party any Merck business or facility that includes any of our proprietary materials, information or technology, we have the right to conduct an audit of Merck's facilities to confirm that all of our proprietary materials, information and technology have been destroyed. The Merck CodeEvolver^® Agreement contains indemnification provisions under which Merck and we have agreed to indemnify each other against certain third party claims. The up-front license fee of $5.0 million is being recognized ratably over a two-year period. We recognized license fees of $0.6 million and $1.9 million for the three and nine months ended September 30, 2016, respectively, compared to $0.4 million for the three and nine months ended September 30, 2015, as biocatalyst research and development revenues and had a deferred revenue balance from Merck related to the Merck CodeEvolver^® Agreement license fees of $2.1 million at September 30, 2016 and $4.0 million at December 31, 2015. 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 substance 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. In August 2016, we and Merck amended the Sitagliptin Catalyst Supply Agreement to prospectively provide for variable pricing based on the cumulative volume of sitagliptin purchased by Merck under the Sitagliptin Catalyst Supply Agreement and to allow Merck to purchase a percentage of its requirements for sitagliptin from a specified third-party supplier. Merck has the right to terminate the Sitagliptin Catalyst Supply Agreement at any time after January 1, 2018 by giving us 24 months’ advance written notice. The Sitagliptin Catalyst Supply Agreement requires Merck to pay an annual license fee for the rights to the Sitagliptin technology each year for the term of the agreement. Amounts of annual license fees are based on contractually agreed prices and are on a declining scale. Prior to December 2015, the aggregate license fee for the initial five year period was being recognized ratably over the initial five year term of the Sitagliptin Catalyst Supply Agreement as collaborative research and development revenue. Due to the amendment entered in December 2015 as noted above, we revised our performance period in December 2015 and began recognizing the remaining unamortized portion of the license fee and the aggregate license fees for the second five year period over the revised period on a straight line basis. We recognized license fees of $0.3 million and $1.0 million for the three and nine months ended September 30, 2016, respectively, and $0.5 million and $1.5 million for the three and nine months ended September 30, 2015, respectively, as biocatalyst research and development revenues. We had a deferred revenue balance from Merck related to license fees of $1.7 million at September 30, 2016 and $1.0 million at December 31, 2015.

Collaborative Arrangements

GSK Platform Technology Transfer, Collaboration and License Agreement

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

We received a $6.0 million up-front licensing fee upon signing the GSK CodeEvolver^® Agreement and subsequently a $5.0 million non-creditable, non-refundable milestone payment upon achievement of the first milestone in 2014. In September 2015, we achieved the second milestone of the agreement and earned milestone revenue of $6.5 million. In April 2016, we completed the full transfer of the CodeEvolver^®protein engineering platform technology and earned milestone revenue of $7.5 million, for which payment was received in June 2016. We also have the potential to receive additional contingent payments that range from $5.75 million to $38.5 million per project based on GSK's successful application of the licensed technology. The contingent payments are not deemed substantive milestones due to the fact that the achievement of the event underlying the payment predominantly relates to GSK's performance of future development and commercialization activities.

We are eligible to receive royalties based on net sales, if any, of a limited set of products developed by GSK using the CodeEvolver® protein engineering technology platform.

The term of the GSK CodeEvolver^® Agreement continues, unless earlier terminated, until the expiration of all payment obligations under the GSK CodeEvolver^® Agreement. GSK can terminate the GSK CodeEvolver^® Agreement by providing 90 days written notice to us.

Under the GSK CodeEvolver^®Agreement, the significant deliverables were determined to be the license, platform technology transfer, and contingent obligation to supply GSK with enzymes manufactured by us at GSK’s expense. We determined that the license did not have stand-alone value. In addition, we determined that the license and the platform technology transfer and our participation in joint steering committee activities in connection with the platform technology transfer represent a single unit of accounting. Our participation in the joint steering committee does not represent a separate unit of accounting because GSK could not negotiate for and/or acquire these services from other third parties and our participation on the joint steering committee is coterminous with the technology transfer period. Amounts to be received under the supply arrangement, if any, described above will be recognized as revenue to the extent GSK purchases enzymes from us.

The up-front license fee of $6.0 million was being recognized ratably over the technology transfer period of three years since July 2014. As the technology transfer was completed earlier than anticipated, we recognized license fees of $0 and $3.0 million for the three and nine months ended September 30, 2016, respectively, compared to $0.5 million and $1.5 million for the three and nine months ended September 30, 2015, respectively, as biocatalyst research and development revenues. We had a deferred revenue balance from GSK related to the upfront license fee of $0 at September 30, 2016 and $3.0 million at December 31, 2015.

In September 2016, we recorded our first project-specific contingent fee based on GSK's successful application of our technology in an existing pharmaceutical product.

Merck Platform Technology Transfer and License Agreement

In August 2015, we entered into a CodeEvolver^® platform technology transfer and license agreement (the "Merck CodeEvolver^® Agreement") with Merck. The Merck CodeEvolver^®Agreement 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, which is being recognized ratably over the estimated platform technology transfer period of two years. In September 2015, we achieved the first milestone under the Merck CodeEvolver^® Agreement and earned milestone revenue of $5.0 million. In September 2016, we completed the full transfer of the engineering platform technology and earned milestone revenue of $8.0 million. We received the $8.0 million milestone payment in the fourth quarter of 2016. Following the completion of the technology transfer, we may be eligible 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.

Under the terms of the Merck CodeEvolver^®Agreement, we granted to Merck a non-exclusive worldwide license to use the CodeEvolver^® protein engineering technology platform to research, develop and manufacture novel enzymes for use by Merck in its internal research programs ("Merck Non-Exclusive Field"). The license to Merck is exclusive for the research, development and manufacture of novel enzymes for use by Merck in the chemical synthesis of therapeutic products owned or controlled by Merck ("Merck Exclusive Field"). Merck has the right to grant sublicenses to affiliates of Merck and, in certain limited circumstances, to third parties. We also granted to Merck a license to make or have made products manufactured using the CodeEvolver^® protein engineering technology platform with a right to grant sublicenses solely to affiliates of Merck, contract manufacturing organizations and contract research organizations. The manufacturing license is exclusive in the Merck Exclusive Field and non-exclusive in the Merck Non-Exclusive Field. The licenses are subject to certain limitations based on pre-existing contractual obligations that apply to the technology and intellectual property that are the subject of the license grants. The licenses do not permit the use of the CodeEvolver^® protein engineering technology platform to discover any therapeutic enzyme, diagnostic product or vaccine. In addition, Merck is prohibited from using the CodeEvolver^® protein engineering technology platform to develop or produce enzymes or any other compounds for or on behalf of any third parties except in a very limited manner when Merck divests a therapeutic product that is manufactured using an enzyme developed using the CodeEvolver^® protein engineering technology platform.

Under the Merck CodeEvolver^® Agreement, we transferred the CodeEvolver^® protein engineering technology platform to Merck over the period from August 2015 through September 2016. As part of this technology transfer, we provided to Merck our proprietary enzymes, proprietary protein engineering protocols and methods, and proprietary software algorithms. We are providing additional enzyme evolution services to Merck at our laboratories in Redwood City through November 2016. The remaining deferred revenue relating to the upfront payment will be recognized upon completion of the additional enzyme evolution services.

The licenses to Merck are granted under patents, patent applications and know-how that we own or control as of the effective date of the Merck CodeEvolver^® Agreementand that cover the CodeEvolver^® protein engineering technology platform. Any improvements to the CodeEvolver^® protein engineering technology platform during the technology transfer period are also included in the license grants from Codexis to Merck. Following the technology transfer period, Merck can exercise annual options that, upon payment of certain option fees, would extend Merck's license to include certain improvements to the CodeEvolver^® protein engineering technology platform that arise during the three-year period that begins at the end of the technology transfer period.

Under the Merck CodeEvolver^® Agreement, we will own any improvements to our protein engineering methods, processes and algorithms that arise and any enzyme technology or process technology that are developed during a technology transfer project, an evolution program or additional services. Merck will own (the "Merck-Owned Technology") (a) any enzyme technology that is developed solely by Merck under the Merck CodeEvolver^® Agreement using the CodeEvolver^® protein engineering technology platform (a "Project Enzyme") and (b) the methods of use of any Project Enzyme or any enzyme developed jointly by Merck and us using the CodeEvolver^® protein engineering technology platform. Merck granted to us a worldwide, non-exclusive, fully paid-up, royalty-free license, with the right to grant sublicenses, to use the Merck-Owned Technology outside of the Merck Exclusive Field.

For each API that Merck manufactures using an enzyme developed with the CodeEvolver^®protein engineering technology platform, we will have a right of first refusal to supply Merck with the enzyme used to manufacture the API if Merck outsources the supply of the enzyme. Our right of first refusal applies during the period that begins on the completion of a phase III clinical trial for the product containing the API and ends five years following regulatory approval for such product.

The Merck CodeEvolver^® Agreement has a term that continues, unless earlier terminated, until the expiration of all payment obligations under the agreement. Merck may terminate the Merck CodeEvolver^® Agreement by providing 90 days written notice to us. We can terminate the Merck CodeEvolver^® Agreement by providing 30 days written notice to Merck if we determine, pursuant to our contractual audit rights under the Merck CodeEvolver^® Agreement, that Merck has repeatedly failed to make required payments to us and/or materially underpaid us an amount due under the Merck CodeEvolver^® Agreement. In the event the Merck CodeEvolver^® Agreement is terminated earlier by Merck, or by us due to an uncured material breach by Merck, or if Merck sells or transfers to a third party any Merck business or facility that includes any of our proprietary materials, information or technology, we have the right to conduct an audit of Merck's facilities to confirm that all of our proprietary materials, information and technology have been destroyed. The Merck CodeEvolver^® Agreement contains indemnification provisions under which Merck and we have agreed to indemnify each other against certain third party claims.

The up-front license fee of $5.0 million is being recognized ratably over a two-year period. We recognized license fees of $0.6 million and $1.9 million for the three and nine months ended September 30, 2016, respectively, compared to $0.4 million for the three and nine months ended September 30, 2015, as biocatalyst research and development revenues and had a deferred revenue balance from Merck related to the Merck CodeEvolver^® Agreement license fees of $2.1 million at September 30, 2016 and $4.0 million at December 31, 2015.

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 substance 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. In August 2016, we and Merck amended the Sitagliptin Catalyst Supply Agreement to prospectively provide for variable pricing based on the cumulative volume of sitagliptin purchased by Merck under the Sitagliptin Catalyst Supply Agreement and to allow Merck to purchase a percentage of its requirements for sitagliptin from a specified third-party supplier. Merck has the right to terminate the Sitagliptin Catalyst Supply Agreement at any time after January 1, 2018 by giving us 24 months’ advance written notice.

The Sitagliptin Catalyst Supply Agreement requires Merck to pay an annual license fee for the rights to the Sitagliptin technology each year for the term of the agreement. Amounts of annual license fees are based on contractually agreed prices and are on a declining scale. Prior to December 2015, the aggregate license fee for the initial five year period was being recognized ratably over the initial five year term of the Sitagliptin Catalyst Supply Agreement as collaborative research and development revenue. Due to the amendment entered in December 2015 as noted above, we revised our performance period in December 2015 and began recognizing the remaining unamortized portion of the license fee and the aggregate license fees for the second five year period over the revised period on a straight line basis.

We recognized license fees of $0.3 million and $1.0 million for the three and nine months ended September 30, 2016, respectively, and $0.5 million and $1.5 million for the three and nine months ended September 30, 2015, respectively, as biocatalyst research and development revenues. We had a deferred revenue balance from Merck related to license fees of $1.7 million at September 30, 2016 and $1.0 million at December 31, 2015.